


Betwixt the Blackout Curtain

by Ikira, SpiritusRex



Series: Tadashi's Guide to the Other Side [1]
Category: Big Hero 6 (2014)
Genre: And several other supernatural and mythological creatures as well, And with all the fun powers that come with being a ghost, Gen, He is learning to deal with it, Here there be dragons, Mrs Matsuda is both awesome and scary, Supernatural AU - Freeform, Tadashi might be slightly dead, There's a learning curve, but that's okay!, ghost au
Language: English
Status: Completed
Published: 2015-01-17
Updated: 2015-03-15
Packaged: 2018-03-08 00:03:31
Rating: General Audiences
Warnings: Major Character Death
Chapters: 10
Words: 58,855
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3188258
Author URL: https://archiveofourown.org/users/Ikira/pseuds/Ikira, https://archiveofourown.org/users/SpiritusRex/pseuds/SpiritusRex
Summary: <blockquote class="userstuff">
              <p>Tadashi Hamada assumed, like most people, that once you died that was it. You’re done. End of story, do not pass GO, do not collect $200, everyone go home.</p><p>He’s wrong, of course</p><p>Tadashi wakes up after his death, which is already pretty unexpected, and is suddenly thrown into the unseen side of San Fransokyo, where Oni walk the streets window shopping, and you can buy potion ingredients for a reasonable price, so long as you have the right currency. He must learn how to not only navigate this strange new world of supernatural creatures, but how to master his own powers now that he’s become one of them. And of top of that, he’s still worried about Hiro, who can’t see him no matter what Tadashi tries. It’s more than a little overwhelming for a guy.</p><p>But Tadashi will have to learn fast, because an evil spirit named Yokai will soon arrive and threaten everything he cares about…</p>
            </blockquote>





	1. Prologue

Tadashi Hamada couldn’t really remember the last few moments of his life in any detail. There had been heat, and light, and smoke filling his lungs until he was choking on it. He faintly remembered something falling from above and hitting him in the head, knocking him to the ground and leaving him stunned. There was a period of darkness and uncertainty, and then he woke to the smell of burning flesh and searing pain all over his body. He remembered looking up, and seeing someone standing over him, though he couldn’t make out their face through the smoke and the tears in his eyes. Then, there was more bright light, and pressure and noise and pain.

And then there was nothing.

+++

Robert Callaghan remembered the last few moments of his life clearly. He remembered staring down at his favourite student, pinned beneath a fallen beam and slowly burning to death. He remembered feeling mild pity at the waste. Tadashi had always been such a brilliant, hardworking student. But not as brilliant as he’d thought apparently, if he’d been stupid enough to run into a burning building and get himself killed. Even though he wasn’t dead yet, Robert was sure the boy would sucumb to his injuries soon enough, and he didn’t have time to help. He still needed to retrieve the neurocranial transmitter for Hiro’s microbots if he wanted to take them and use them for his revenge. Krei’s presence at the showcase tonight had only furthered his desire to destroy the man who had taken his daughter from him. So Robert turned away from Tadashi and his whimpers of pain, already dismissing the boy from his mind as he went to retrieve the headband that laid abandoned on the side of the main stage.

But Robert hadn’t realized how quickly the fire he’d set had spread, and he’d failed to account for the large tanks of compressed air that had been set aside for one of the devices that had been shown off earlier in the show. Before he’d known what was happening, the tanks had exploded with enough force send a shockwave through the building that leveled everything that hadn’t already been destroyed by the fire.

Robert wasn’t sure if it was the explosion, or the shrapnel, or the roof collapsing that actually killed him. Either way, he’d woken up afterward to the sight of his own body below him, and immediately knew he was dead.

At first, he’d been upset, as was natural for someone who’d just died. Then he’d started wondering why he was still here, and if this truly was all there was to life after death. He’d never been one for religion, but he’d always assumed that there was at least _something_ beyond. This was not what he’d expected at all. But then it occurred to him that if this was truly the afterlife, then surely Abigail would be here with him, wouldn’t she?

But she wasn’t, that he was quick to see. Perhaps she wasn’t here, he thought, because she had died in some strange portal that _Krei_ had created, leaving her trapped in some other world. Robert felt his heart clench in pain and despair. Even in death, his little girl was lost to him.

Almost immediately his old rage returned, burning away the shock of his death and his grief. The rage was familiar, comforting, and he clutched the emotion to his chest like a lifeline. He was dead, but he refused to move on until he’d gotten his revenge. He refused to pass quietly into the night while Krei still walked free.

His mind then went to his original plan, stealing Hiro’s microbots and using them to get his revenge, but he almost immediately discarded it again. He doubted the neurocranial transmitter would work for a dead man. Such a pity, considering all the effort he’d put into starting the fire to cover his tracks in the first place. Such a waste. But he was flexible, and patient, and absolutely driven by his need for vengeance. He’d think of something else. He would find a way to make Krei suffer.

He set his mind to working on new plans for revenge as he started to walk away from the ashes of the showcase hall, and the remains of his life, already deep in thought. But when he reached the gaping hole in the wall where the south corner of the building had collapsed in the explosion, a flash of white caught his attention. It was like a beacon of white in the dark ashes of the hall, immediately drawing his eye like a moth to flame. Curious, despite himself, he bent down to try to pick the object up from where it was half-buried in soot.

It took a few tries to get it free. He’d forgotten for a moment that he was nothing more than a ghost now, completely intangible, and had been rudely reminded when the first time he tried to touch the object his fingers had passed right through. But something told him that he _needed_ to see what it was, and so he didn’t allow that to discourage him. With a little trial and error, he found that if he concentrated, he could make contact with it, and once he found purchase he pulled the object loose with a tug. Slightly tired from his exertions, but feeling quite pleased with himself regardless, he held the object up to the pale moonlight shining through where the roof used to be to get a closer look at it.

It was a Kabuki mask. He wasn’t sure what such an object was doing at a science fair of all things, but they weren’t exactly rare items in this city. The golden eyes stared up at him almost accusingly as he traced his fingertips over the red painted lines. He had never been much of a fan of the Kabuki art form, despite its popularity in San Fransokyo’s theater districts, but he’d picked up enough about it simply from living in the city to recognize the design as a hero’s mask. Immediately his mind went to the comic book superheroes he’d practically worshiped as a child, the heroes disguising their identities as they gained vengeance on the criminals of the city. He chuckled to himself as he stared down at the mask. It was almost too fitting, a voice whispered in the back of his mind. _It’s perfect_.

With a satisfied smile, he placed the mask over his face as he headed out into the night. Even if he was dead now, he was determined to find a way to take down Krei and get his revenge, revealing the man for the true criminal he was just long enough for Krei to suffer as Robert had suffered.

And then he was going to make Krei join him in the afterlife.

Robert was so focused on his thoughts of revenge he didn’t notice the shadows of the building suddenly thickening around him like a living thing, a sound like the faintest whispers growing from within them. The darkness _shifted_ as he crossed the threshold of the ruins, moving and flowing along the floor and through the rubble like liquid smoke to spread across the entire area. As they travelled, they started absorbing every one of the discarded microbots that had been scattered from the explosion, pouring into all the cracks and crevices to ensure they didn’t miss a single one. Robert didn’t notice this, nor did he see the shadows coalesce into solid tendrils once they were finished absorbing the microbots. They started following him like a loyal dog, the whispering noises becoming stronger. He also couldn’t see the green and purple veins spreading across his body like a virus as his mind became consumed with nothing but the desire for revenge.

Robert was luckily also too distracted to see a soft glow suddenly appear hovering over the ashes of the showcase hall, a trio of ghostly blue flames swirling around it like moons as it slowly started to take human shape.

By the time the ghost of Tadashi Hamada had fully materialized, Robert Callaghan was long gone.


	2. Awakening

It was a bright light shining in Tadashi’s eyes that finally dragged him back to consciousness. At first he’d simply tried rolling away from the offending brightness, figuring he’d accidentally forgotten to close his blinds the night before, or that he’d fallen asleep in his lab again, and the brightness was just sunlight. But then he’d realized that the sun wasn’t usually _blue_ , or at least he was pretty sure it wasn’t, and the light stabbing at his closed eyelids definitely had a blue tone to it. Maybe Hiro was pulling another prank on him? Man, if he woke up to the cat wearing hover boots again, he was going to hide all of Hiro’s tools for a _month_.

But when he finally opened his eyes, it wasn’t to Mochi hovering over him, or Hiro shining a flashlight in his eyes with a devious expression, or any of his little brother’s usual tricks. It was to a flickering ball of blue flame beaming its light cheerfully into his face.

There was a moment where Tadashi’s mind couldn’t quite compute what it was seeing, and he simply laid there and stared at the flame. And then all at once his memories came rushing back. Hiro’s presentation. The talk on the bridge. The screaming and sirens. Professor Callaghan.

The fire.

Tadashi screamed and jerked back on instinct, the memory of burning pain flashing through his mind. To his horror, the blue flame seemed to follow him, and when he looked around, there were two more nearby. He tried to scramble away from them, but it seemed that no matter how far he moved, the balls of fire followed. To an outsider it probably looked almost comical, the way he ran to and fro, trying to get away from them, but they followed cheerfully along without trouble no matter how far or fast he ran.

He finally gave up after a few minutes and stopped to catch his breath, leaning against the remains of a support pillar. He glared at the balls of fire in annoyance, too tired at the moment to be properly afraid of them. Besides, he’d realized by now that they weren’t hurting him, nor were they coming any closer to him than a few feet away, seemingly content to just hover nearby. Instead, he glanced around, trying to figure out what had happened to him. The showcase hall was completely gutted, nothing more than a burned out husk, with a few fires still smouldering here and there. He could remember the fire, remembered getting hit on the head by something, but when he glanced down at himself, he could see no sign of injury. How was that possible?

It was only then that it occurred to Tadashi that the strange blue flames had been _hovering_ nearby him this whole time, floating somewhere between four and five feet off the ground around his shoulder height. A sinking feeling grew in his gut as he realized what the strange flames reminded him of, an old memory floating to the top of his mind. He remembered pouring over an old book his mother had given him for his birthday one year, back when she was trying to ensure he experienced just as much of her culture as his father’s. It had been full of stories and myths from her home country, all beautifully illustrated with ink paintings.

The one picture he remembered now was of a pale woman dressed in a white kimono, her long black hair hanging down across her face like a curtain. And surrounding her had been a pair of floating balls of fire, called hitodama if he remembered correctly.

The book had called the woman a Yurei. A ghost.

And just like that it hit him. He was dead.

He took a deep breath. And then another. His hands were starting to shake slightly, and he was sure his eyes were wide enough to see the whites all around them, but he was a bit too caught up on the fact that he’s dead to care. He died. He’d _died_ , he was dead, he was dead and he didn’t know what to do or what had happened, he was just _dead_ and...and…

He flinched as the hitodama flickered strangely and then a pile of nearby embers suddenly burst back into full flame, crackling cheerfully to life. He quickly moved away from the fire, uncomfortable around it even if it could no longer hurt him. Thankfully the distraction was enough to jolt him out of his panic and get his mind working again. Losing his head was not helpful at this point, he needed to think. He’d died, obviously, but how? What did he remember?

He remembered the fire. He remembered the pain and fear. And suddenly he remembered the other person, standing over him, just watching. He couldn’t remember who it was or if he’d seen their face, but he did remember that he’d reached out to them. And they’d turned away. They’d left him to die.

A violent and unexpected rage suddenly overtook him. They’d _left_ him, even as he’d cried out for help. How _dare_ they! If they’d helped him, he might not be dead now! He wanted to find this person, find them and make them _suffer_ for what they’d done to him.

But almost as soon as the rage came, Tadashi forced it down. He was left standing there and breathing heavily, the feeling leaving him scared and breathless with its intensity. He’d never felt so hateful in his life, even after his parents had died and he’d been brought to live with his Aunt that he barely knew. It left him feeling shaky and afraid, uncertain where it had even come from. He wasn’t like that. That wasn’t him.

With almost physical effort, he banished the angry thoughts from his mind. He told himself that there was no guarantee that the person would have been able to save him, and besides, it wouldn’t change anything now anyways. What was done was done. He was dead, and there was no changing that.

He took a deep breath and closed his eyes, focusing on trying to stay calm. He drew on all of his experience getting past his frustrations while working on Baymax, took another deep breath, and allowed the dark thoughts to flow away like water. By the time he reopened them his misplaced rage was gone, and he felt much calmer. Now that he was thinking clearly, he remembered that he’d left Hiro behind when he’d run into the building after Professor Callaghan.

“Oh god, Hiro!” Tadashi shouted, wanting to smack himself for not thinking of his brother sooner. He frantically started searching for the main doors, hindered slightly by how little the remains of the building resembled the intact structure, but he thought he could see them not too far away. He ran for them immediately, ignoring the way the hitodama followed, and that he was passing through any obstacles in his path rather than going around them. He was dead and in a hurry, he didn’t have time for walls.

When he came out into the plaza at the front of the building, the first thing that he noticed was how empty it was. There was a single police car waiting on the street, and a line of police tape surrounding the area, but for the most part there was no one there. He glanced across the University campus at the huge clock hanging over the main gate, and gasped when he realized how much time had passed. It was well into the wee hours of the morning, almost dawn, and Hiro must have been taken home by now. At least he better have been, because Tadashi was not willing to consider the alternative.

The University campus was a good twenty minute ride by his moped, so the walk would be closer to an hour and a half, but Tadashi wasn’t sure what his alternatives were. It wasn’t like he could hail a cab. So with no better plans at that point, Tadashi simply started walking home. The bright spotlights of the campus made way for dimmer streetlamps and the burning neon of the city as he walked, his head down and his mind carefully blank. He was trying very hard to not think about what would happen once he _did_ get home. His only concern right now was making sure Hiro was okay.

He was so focused on not thinking about anything that at first he didn’t notice the change. He’d just been absently thinking to himself that the city seemed a little bit more crowded than usual, especially considering the late hour. It wasn’t until he actually ran into someone that he finally spotted what had changed.

He stumbled back from the impact, completely caught off guard. He was a ghost, wasn’t he? Shouldn’t he have passed right through the person, just as he had through the walls in the showcase hall? Still, he instinctively started to apologize, his politeness just as much a part of him as his arms or eyes. But then he finally looked up properly at the person, and the apology died on his lips.

It was an Oni. Or, at least it looked exactly like one, down to the blue skin and tiger print loincloth. It was looking right at him with one raised eyebrow, like it could see him as well as touch him. Normally Tadashi would have dismissed it as someone in a very convincing and elaborate costume, but considering he still had a trio of hitodama floating around his head and he was pretty sure he was a ghost, something told him this wasn’t a costume. The Oni grunted at him and shifted its grip on the iron club it was carrying, bringing it up to a more threatening position.

Recognizing that he was seconds away from being clobbered, Tadashi acted quickly, even as his mind screamed at him that this was impossible. He firmly told his mind to _shut up_ for a minute, and then bowed low and respectively, even though it exposed the back of his neck to the creature. “Forgive me, sir. I was not watching where I was going.”

He waited for one breathless moment, eyes fixed firmly on the pavement below his feet and a cold sweat building up on forehead. He expected to feel the impact of a blunt weapon to his head and neck at any second, already subconsciously bracing himself for the blow, a thousand stories of violent man-eating Oni he’d heard as a child dancing through his head. But when the blow didn’t come, he dared to peek upwards. He was both shocked and relieved to see the Oni simply roll its eyes at him, and dismiss him with a wave, already returning its attention to the nearby shop windows it had been eyeing before. Tadashi rose from his bow with a shaky sigh of relief, but before he could say anything else the Oni scoffed at the window’s wares and lumbered off, dragging its iron club along behind it with ease into the swarms of people filling the street. Tadashi watched it go, more than a little shocked at how quickly it seemed to vanish into the crowd. Shouldn’t they have noticed the giant monster walking among them? Shouldn’t people be freaking out? But then he actually _looked_ at the crowd for the first time. He couldn’t help gasping in shock.

Although he clearly recognized the street he was standing on as one of the main roads heading through the city, it was almost like a completely different world. The usual crowds of people were interspersed with people and creatures straight out of mythology and fantasy movies, and Tadashi could do nothing but stand and stare and watch it all go by as he tried to take it all in. A group of people who could only be a family of Tengu were walking down the opposite side of the sidewalk, the woman holding a young black-winged child in her arms even as she chatted up the long nosed man walking alongside them. A pair of red and blue Oni were standing on the street corner arguing about something, while a skeleton steered a gondola full of what looked like ghosts down the street as if it was actually a river. Above him a trio of women dressed in black and wearing pointed hats zoomed by riding brooms, with colourful paper lanterns hanging from the handles to light their way. Zig-zagging above the crowds were more hitodama, being herded along by a tiny person with gossamer butterfly wings carrying a shepherd’s staff. He was forced to jerk back as an inhumanly beautiful woman with long black hair and dressed in a white kimono ran by, leaving a trail of snowflakes in her wake that melted almost as soon as they formed. He ended up stumbling backwards a bit, almost falling into a shop that he’d never seen before, despite driving down this very street every day to get to class and back home. The storekeeper looked up at him and grinned, and if her single eye and jagged teeth weren’t enough to make Tadashi nervous, here wares were. Various herbs and crystals shared shelf space with bones, dried up animal parts, and dusty glass bottles filled with strange colourful liquids. Tadashi hastily made his way back to the street.

It was all so beautiful and impossible, like something out of a dream, Tadashi thought to himself in a daze. Everywhere he looked, there was something new to see, some new magical creature or person or thing, and he could feel himself getting overwhelmed. His hitodama suddenly flashed threateningly, making him flinch and Tadashi quickly excused himself down a side alley to calm himself before he hyperventilated. He could at least get away from all of the strange sights, even if he couldn’t escape the hitodama which were still making him slightly nervous.

He walked about halfway down, far enough away from the main street that he could no longer hear the hustle and bustle, so he could at least catch his breath in peace. It was so overwhelming, seeing this strange new side of San Fransokyo, and he couldn’t help but wonder if it had always been like this and he’d just never known, or if this was some strange afterlife that just looked like his home city. How could he have missed all of this if this was all real? Surely there would have been some sign!

He didn’t have time to ponder that much further though, because at that moment he realized he wasn’t quite as alone as he’d thought. His head shot upwards when he heard growling coming from deeper into the alley. At first, he only spotted a mangy looking stray dog down in the shadows at the end of the narrow space, big for a mutt, but not something Tadashi was too afraid of. But then suddenly it raised its _heads_ and Tadashi was a whole lot more concerned. That was a _lot_ of teeth. With a yelp, he ran out of the alley, the cerberus’ loud barks chasing him the whole way up the street.

He could hear people laughing at him as the cerberus chased him up the street, but he found he didn’t really care. He wasn’t sure if the three-headed dog could hurt him like this or not, but he wasn’t eager to find out. Those teeth had looked _sharp_. Thankfully most of the creatures and monsters got out of his way as he dashed by, and those that didn’t move he tended to pass right through. Those must have been the normal people, he supposed, because they didn’t seem to react to his presence at all.

He was halfway uptown, closer to home than the University now, when the cerberus finally caught up to him. Tadashi skidded to a halt when a second hell beast suddenly jumped out of a nearby street, cutting him off. A third dog approached him from the left, leaving him pinned up against a storefront that he could have sworn was abandoned when he was alive, but now seemed to be selling painted masks that were blinking at him. Tadashi wasn’t much paying attention to the masks though, too distracted by the dogs that were slowly circling closer, their many shiny fangs bared and foam dripping from their jowls. The leader tensed to leap, and Tadashi flinched back.

It never struck though, because at that moment a small round blurr dropped down from the awning over the mask shop and landed on the cerberus’ back, hissing and spitting. The cerberus let out a high-pitched yelp, and started bucking wildly, trying to knock its attacker off. The other beasts approached to help, but another hiss and the swipe of a claw across the nearest one’s muzzle caused them to jump back yelping. Finally the leader managed to snap one set of jaws close enough to the attacker to knock it loose, and the blurr landed on the sidewalk between Tadashi and the dogs, still hissing and yowling.

Tadashi couldn’t believe his eyes, but there was no mistaking that distinctive pattern of fur and familiar rounded body. It was Mochi, their big fat calico cat who seemed to do nothing but sleep and eat and sleep some more. _Mochi_ was standing between him and three hell dogs almost four times the cat’s size, his mottled fur puffed up and his tail bristling big enough to look like two tails in one. The lead cerberus growled and started to approach again, but Mochi batted at its face, hissing even louder, and the cerberus backed off. Eventually the dogs decided it wasn’t worth the effort, because they slunk off back the way they’d come, their thin bony tails tucked between their legs. Tadashi watched them go for a minute until he was sure they were gone, and only then did he crouch down.

“Thanks, buddy. I think you just saved my life. Or death, I guess,” he told the cat, even as he reached out to rub Mochi’s head between the ears just like the cat had always preferred. To his mixed relief and confusion, his hand connected, and he could feel Mochi’s soft fur underneath his fingers, still puffed up. A few quick brushes of his hand fixed that though, and soon Mochi was his usual soft self, purring happily under Tadashi’s ministrations. Maybe ghosts could just pet cats? Tadashi didn’t bother to think too hard about it, just happy to see _something_ familiar after the insanity from earlier.

“There. Better?” he asked the cat absently, scritching him under the chin.

“Oh, yes,” Mochi said, eyes falling shut in pleasure. “Much better. I always hate having to groom after dealing with those ruffians, my fur lays funny for _days_.”

Tadashi blinked at Mochi for a moment, his hand frozen mid-scratch. Had Mochi just…?

“Oh, why did you stop?” Mochi whined, blinking up at him in annoyance. “You just found the good spot!”

“Aah!” Tadashi yelped, falling backwards onto his butt and scrambling away. Mochi sailed through the air with an angry yowl, but landed safely on his feet on the sidewalk. “You talked!” Tadashi pointed an accusing finger at the cat, his eyes wide in shock.

Mochi sighed in an irritated manner, before slowly walking closer. As he moved, his tail swung in sinuous arcs behind him, bringing it to Tadashi’s attention. The ghost was shocked to see that Mochi’s usually stubby bob tail was now much longer and thinner, and forked about halfway down. Tadashi gulped at the sight. His old mythology book had also had a section on the cat monsters known as Nekomata, talking cats with forked tails who had lived for a hundred years and could influence the dead. He wondered what that would mean for _him_ now that he was one of the dead himself.

But Mochi was looking at him with a fond expression, and when he reached Tadashi’s side, he simply crawled into his lap as he always had, curling up and purring. Slowly, Tadashi relaxed, starting to pet Mochi absently as he usually did.

“Hmm, yes, that’s better,” Mochi said after a while, and it was a sign of how much Tadashi had been through this evening that he didn’t even jump again. “Sorry to startle you, but there wasn’t exactly a way to break it to you gently.”

“You’re a nekomata,” Tadashi murmured, more a statement than a question.

Mochi nodded happily. “Why, yes I am. Glad to see you remember some of your mother’s heritage, though I was starting to think you’d given up on it. Too bad you had to die before you’d fully learned everything, but I suppose learning by immersion is a way to do it too. You’ll certainly learn more quickly, that’s for sure. Ah, but I’m getting ahead of myself,” Mochi quickly said with a chuckle. He glanced up at Tadashi, his bright green eyes cheerful, but that cheer quickly melted away when he spotted Tadashi’s expression.

The young man was staring blankly down at the ground, his breath hitching, and tears starting to slide down his cheeks. It looked like he’d barely heard a thing Mochi had said. All of the combined events of the night, his death, the transformed city, the cerberus attack, Mochi talking, had finally pushed Tadashi to his breaking point, and it was all he could do to just sit there and breathe. It was too much.

“Oh. Right, you’re probably a bit overwhelmed at this point. Newly dead, and all. Here,” Mochi leaned up, rubbing his head under Tadashi’s chin, and jolting him slightly. His eyes refocused on Mochi, but the crying didn’t stop. “I’m sorry, Tadashi. Why don’t we just get you home first, and sort out the rest of the details later. Okay?”

Tadashi merely blinked, his expression still empty, his breath still hitching. Mochi gave his chin another affectionate headbut, purring loudly. “Tadashi,” the nekomata called again. “Let’s go home.”

“Home?” Tadashi repeated, and a bit of life started to return to his expression. “Yeah, home. I wanna go home.”

“Then let’s go,” Mochi said simply, hopping out of Tadashi’s lap to sit gracefully on the ground. He waited until Tadashi had slowly stumbled to his feet, wiping the tears from his face and still looking more than a little shell shocked, and then started leading the way home, his forked tail flicking cheerfully with each step. Tadashi kept his eyes on that tail, following it hollowly, and tried very hard not to see anything else around him anymore. He’d had enough craziness for one day, any more and he’d lose his mind.

+++

Thankfully, Mochi took a winding path that seemed to avoid the crowded main roads. It took a bit longer than Tadashi’s usual direct route home though, and so by the time they arrived at the Lucky Cat Cafe, day had broken. It was a grey day though, promising rain, and sure enough the clouds opened up just as Mochi lead the way down the alley next to the building.

Mochi jumped up the side of the side of the alley behind the cafe and pushed himself into the house through a cracked open window. Tadashi followed by simply passing through the back door, into the kitchen of the cafe. He was mildly surprised to find it empty. Usually by this time of day, the cafe would have been bustling, full of businessmen and students picking up their caffeine fix on their way to work and school. The weather _was_ gloomy, but not enough to chase everyone off.

It honestly didn’t occur to him until he arrived upstairs and found a large group of people all wearing black and talking quietly together that Aunt Cass might have closed the cafe because of _him_. Oh god, he was walking into his own wake.

He moved carefully around the groups of people, reluctant to touch them even if they wouldn’t know he was there. Part of him was baffled at the turn out. There were people here he hadn’t seen in years, old classmates or friends he’d lost touch with, some of his professors from school, some of the cafe regulars. There were more people than he’d ever expected to see, and he wasn’t sure how that made him feel. He quickly dismissed the thought though, more focused on finding his family.

He found Aunt Cass near the foot of the stairs leading up to the top floor, surrounded by his friends from SFIT offering her comforting words and condolences. He was momentarily baffled at the sight of GoGo and Fred in formal clothing, but his bigger concern was the empty expression in Aunt Cass’ eyes, and the way she glanced up at the third floor landing. When Tadashi moved towards the stairs he spotted someone at the top just walking away. Almost immediately after, Mochi appeared at the top of the stairs, looking down at him with eyes that almost seemed to glow in the dim lighting, before trailing after the person. Tadashi knew what that meant.

His feet felt like they were made of lead as he slowly walked up the staircase leading to his and Hiro’s shared room. Well, Hiro’s room now, he supposed. It wasn’t like _he_ would need it anymore. Still, considering he’d walked this route pretty much every day of his life, it should not have been this hard. It felt like it took an hour just to reach the landing, every step made through sucking quicksand. But he made it. When he stepped fully into the room, his heart twinged painfully at what he saw.

His side of the room was just as immaculate as ever, his bed still perfectly made and his books and desk still in order. It was like he’d never left, even though it must have been days since the fire if they’d already had his funeral. But Hiro’s side of the room…

Hiro’s side of the room had always been messy, but now it was _trashed_. Hiro’s sheets were all ripped off and tossed aside, his clothes had been thrown everywhere, a few of his action figures had been smashed, and it looked like he’d knocked everything off of his desk onto the floor in one violent motion. There wasn’t one part of Hiro’s stuff that looked untouched. It was like a whirlwind of destruction has passed through, leaving disaster in its wake.

As for Hiro himself, he was the complete opposite. Tadashi found him standing perfectly still in the middle of the room with his back to the staircase, clutching an envelope in his hands. Mochi was winding himself around Hiro’s ankles, purring, but Hiro was ignoring the cat completely. Something made Tadashi approach with caution, something about the uncomfortable stiffness to Hiro’s shoulders, or the way he barely seemed to be breathing. Tadashi stepped carefully around the mess on the floor, reluctant to disturb any of it, until he’d circled Hiro completely and faced him head on.

Tadashi already felt like his heart was breaking the moment he’d seen Aunt Cass, but now he knew that his earlier pain was nothing compared to this. Hiro was staring down at the envelope in his hands with glassy eyes, his lower lip caught between his teeth as he breathed shallowly. As Tadashi watched, tears started trickling down Hiro’s face, but Hiro didn’t seem to notice them. Instead he tentatively started opening the envelope with shaking fingers, wincing slightly when his finger caught too hard on the edge and tore the paper a little. Tadashi spotted the SFIT seal on the back of it, and realized that this was Hiro’s acceptance letter that he’d received at the showcase right before everything had...before everything. He remembered how this letter had been the culmination of all of Hiro’s hopes and dreams and hard work, but now Hiro was treating it as if it was poisonous. He’d barely opened the flap when his legs suddenly gave out, and Hiro fell to his knees, barely missing Mochi in the process. The cat yowled and scampered off, though not before tossing a meaningful glance in Tadashi’s direction.

Tadashi had no idea what the nekomata wanted from him, but he approached his brother anyways. His hands hovered uselessly over Hiro’s shoulders as they started shaking with silent sobs, completely lost. If he was still alive, his first instinct would be to wrap Hiro up in his arms and hold him until the tears stopped, and then quickly cheer Hiro up by dragging him along to work on some project or take him out for ice cream or make him some treat from the cafe. But he was...not really here now, he couldn’t do any of those things. All he could do was watch and listen and be _useless_.

Despite himself, he lowered his hands with the wild hope that it would be like Mochi, and he’d miraculously be able to touch Hiro. But sure enough his hands passed right through Hiro’s shoulders, like the ghost he was. For a wild moment he thought that maybe Hiro _had_ somehow felt his presence, had realized that he was in the room with him, because Hiro’s breath hitched for a moment when he made contact. But then Hiro shuddered and started crying even _harder_ , like Tadashi’s presence was upsetting him even more, and Tadashi immediately moved away.

Suddenly he felt himself starting to cry again too. He was only making things worse by being here, what was he hoping to accomplish? He didn’t want to see this, didn’t want to stand here and watch as his little brother broke down crying over _his_ stupid mistake. This was all his fault. It was because of him, him and his stupid need to be a hero, that his little brother was sobbing into the floor of their bedroom, while his friends and family stood in the rooms below and mourned. This was all his fault and he could do nothing to fix this.

A familiar anger started boiling up inside his chest, though this time it was aimed at himself instead of the stranger in the fire. _He_ had done this, he had made this mess. He turned away angrily, and spotted the showcase poster he’d stapled up for Hiro all those months ago. If he’d never suggested Hiro try out, none of this would have happened. His fault, his fault, all of it. 

In a fit of rage, he reached out for the poster as if to tear it down, forgetting that he couldn’t actually touch it. His hands passed harmlessly through the wall, and Tadashi growled in frustration. He glared hatefully at the stupid paper, wishing he could rip it to pieces, but just then his hitodama suddenly flared up even brighter than before, and before he knew what was happening the poster was on fire.

He stared at the paper in shock for a moment. Had he done that? He vaguely remembered before when he’d been upset in the showcase hall, his hitodama had flared up and a fire had suddenly grown, but at the time he’d assumed that it was just leftover embers from the fire. But where had the fire come from here? He’d been angry at the poster, and then suddenly it caught fire? He _must_ have done it, then, it didn’t make sense otherwise, especially as nothing else in the room was burning and there were no other sources of heat or flame he could see. But he didn’t remember reading anything about ghosts being able to cause fires!

Regardless, he didn’t have time to worry about it, because at that moment Hiro noticed the fire. His sobs suddenly tapered off when he spotted the cheerful flames flickering away, and his eyes instantly became impossibly wide with fear. Tadashi thought he could almost see the reflection of the showcase hall burning in Hiro’s eyes. All of the sudden his little brother was screaming, screaming and shouting and trying to scramble away.

Tadashi frantically wanted to reach out to Hiro, to instinctively try to calm him even if he’d inadvertently caused Hiro’s fear in the first place, but before he could so much as move there was a thundering of footsteps on the stairs and suddenly Aunt Cass was there. She took one look at the room and the fire, taking stock of the situation, and then moved, tossing the tea from her teacup onto the poster with a decisive flick of her hand. Instantly the fire hissed as the cooler liquid spilled over it, and went out.

With the fire taken care of, Aunt Cass abandoned her teacup to Hiro’s dresser while she crouched down to the ground and scooped Hiro up into her arms, just like Tadashi would have done if he could. She cradled him gently as Hiro pressed his face into her shoulder, holding him and rocking him and shushing him gently as he sobbed and shook. Tadashi could see Aunt Cass was trembling slightly too, but she hid it well as she devoted all of her attention to her nephew, not asking any questions, just offering comfort. Hiro cried harder and curled even closer.

As for Tadashi, he’d seen enough. His presence here was nothing but a problem for his family, especially if he was accidentally setting things on fire at a whim. He needed to leave. Now.

He ran past where Aunt Cass and Hiro were huddled next to the stairs, practically flying down to the second level and through his group of friends who had gathered at the bottom when they’d heard Hiro’s scream. He shuddered as he passed through Wasabi’s chest, even though the man didn’t react at all. This was just all too much for him. He needed to get away.

He was halfway through the wall heading out to the back alley when Mochi finally caught up to him. The cat practically landed on his head, yowling irritatedly until he stumbled to a stop leaning against the kitchen counter. Apparently he didn’t phase through surfaces if he didn’t want to. Well wasn’t that convenient.

Mochi was glaring up at him, so he tucked that newfound information away for now. “What?” he glared at the nekomata, not in the mood for more strangeness. He just wanted to _get away_.

Thankfully Mochi seemed to get that, because his expression softened. “Where are you going to go?” he asked gently, his two tails tucked around his paws as he sat in front of Tadashi without a hint of judgement on his face. Tadashi was impossibly grateful for that at the moment.

“I don’t know,” Tadashi admitted after pausing to think about it. “Away? I have a grave now, I’m assuming, maybe I’m supposed to go there. Or aren’t ghosts supposed to haunt where they died? Should I be going back to the University?”

Mochi sighed gently. “No, you don’t have to haunt where you died, or go to your grave. Some Yurei do, some don’t. It’s a matter of preference. Where would you like to go?”

“I...I don’t know. I wanted to go home, but being here...I can’t stay.” Tadashi glanced back up towards the stairs. He wondered if Aunt Cass had managed to calm Hiro down by now or not. Hiro had been pretty upset.

“Hmmm, you’re probably right,” Mochi agreed, also looking towards the upper floor of the house. “You should probably go, at least until you’ve gotten that fire habit under control.”

“I didn’t mean to,” Tadashi said very quietly, guilt making it hard for him to speak past the lump in his throat. He scowled at the hitodama that were still cheerfully orbiting him like little satellites. “I just got angry, and...poof.”

“No, it’s alright,” Mochi quickly reassured him, reaching up as high as he could to pat Tadashi on the shin. “It’s alright. Yurei tend to be very emotional creatures, you’re no exception. Though I must say, I’ve never seen a Yurei with fire powers like yours. Even the Will o’ the Wisps down in the financial district don’t have quite that kind of power.”

“Will o’ the Wisps? No, nevermind, I don’t really want to know right now. Just,” Tadashi’s hands rose to his head, where he’d normally be adjusting his hat in a nervous gesture. But his hat wasn’t there, as it had fallen off before he’d died, and instead all he could do was gesture awkwardly around his head. His hands dropped uselessly to his sides. “Just tell me where I should go where I can’t hurt anyone.”

The nekomata eyed him consideringly. “Well,” he said at length. “I have one old friend who would take you in. Normally sending a handsome young man such as yourself to her house would be to send him to his death, but considering current circumstances, I think you’ll be okay.”

Tadashi surprised them both by snorting at the cat’s poor joke. He hadn’t thought he’d be able to find humor in his situation just yet, especially considering what had just happened, but maybe it was just the surrealness of everything. He was dead, standing in his former kitchen, talking to his cat who was talking back, all while three little balls of flame with the power to set stuff on fire were flying around his head. It was all more than a little ridiculous.

“Alright, just tell me where to find her.”


	3. Discovery

Mochi’s friend turned out to be old Mrs. Matsuda, to Tadashi’s shock. When the cat had told him the address, he hadn’t been sure what to think at first. Though Mrs. Matsuda had been a regular at the Lucky Cat for years, he’d never actually known where she lived. Following Mochi’s directions lead him to the outskirts of the city, closer to the mountain ranges in the Northeast. When he arrived at the address, the house had seemed harmless enough, a typical two level home with a porch and a front flowerbed, though the flowers were looking a bit sad as autumn set in. But then he started walking up the path, and things started to change.

As he glanced around, the flowerbeds seemed to shimmer and shift, until the withered leaves and drooping petals were replaced with lush but bizarre plants in impossible colours that seemed to blink up at him in curiosity. The brick walkway leading up to the house became old cobblestone lined with bronze hanging lanterns that flickered with unnatural green flames. An iron pot large enough to cook a goat resting on clawed feet appeared on the porch, and beside it was a long shovel, crusted with dirt and rust. The appearance of the house itself also changed, becoming more like a traditional japanese structure than the suburban design it had sported before, though it looked run down and aged. The windows were all dark, but he thought he could see a dead chicken hanging in front of one of them by its legs. He felt like there were eyes everywhere, not just in the garden, watching him intently.

Tadashi was seriously considering simply turning tail and running when the door to the house suddenly swung open, revealing Mrs. Matsuda standing there in a ratty old kimono practically hanging open to the world. Tadashi immediately looked away to try to preserve her modesty.

Mrs. Matsuda, however, merely cackled at the sight of him. “Ah, there you are, Tadashi. Mochi told me you’d be by. Come in, come in!” The old lady didn’t give Tadashi time to protest, moving down the pathway far quicker than any 80 year old should be able and grabbing him by the wrist. Before Tadashi could be surprised by this, she was already pulling him into the house with a strength she should not have possessed.

The inside was just as strange as the outside, but much cozier. It was like any old woman’s house, with antique furniture and every other surface covered in doilies, but on top of that her shelves were stuffed full of scrolls and strange talismans, with herbs and dead animals hanging from the ceiling. He could see into her kitchen, where a large stone mortar and pestle were resting on the table next to a long wicked-looking kitchen knife, surrounded by strange ingredients he didn’t want to bother identifying.

Okay, so Mrs. Matsuda was some sort of supernatural creature too. After everything he’d been through, he wasn’t sure why he was surprised. She knew Mochi after all.

While he was coming to terms with this, the old woman was already gesturing him to make himself at home before hobbling towards the kitchen and muttering to herself. Tadashi didn’t follow, instead slowly walking into the nearby sitting area in a bit of a trance as he tried to take in every inch of the strange dwelling. The bookshelves looked to be full of spellbooks, though more than half of them had titles that were written in languages he couldn’t read, so he couldn’t be sure. The grandfather clock in the corner had six hands, and he was pretty sure the pendulum inside was actually a knife. One of the side tables had legs and seemed to be tapping its foot impatiently, while the pictures on the wall kept staring at him.

There was also a black cat sitting on a nearby chair, but he quickly confirmed it only had the one tail. Still, it watched him with more intelligence than he thought a normal cat should have. The coffee table, which thankfully didn’t seem to be alive, was covered in yet another crocheted doily, but it was also host to a crystal ball and what looked like a shrunken human head.

The couch at least looked safe enough, he supposed, so he took a seat there and tried not to touch anything.

Mrs Matsuda came in a few minutes later, bearing a normal-looking tray of tea and cookies. She moved as if to put the tray down on the coffee table, but before she could the side table with legs was dashing towards her, jumping about her feet like an excited puppy. With an irritated huff, the old woman reluctantly placed the tray on its surface, rolling her eyes when the table immediately ran up to Tadashi to offer him the tray.

“Uh, thanks?” Tadashi said questioningly, tentatively reaching out and selecting a teacup and sugar cookie. He wasn’t surprised when he could easily pick up both objects. Everything else in this house seemed to be magic, why not the food? Although as a ghost, he wasn’t completely sure he could actually eat anything. He settled for sipping lightly at the tea, and found he could at least manage that much, although it didn’t taste like any tea Tadashi had tried before. At his feet the table seemed to be watching Tadashi, waiting for something. “Um…?” Tadashi glanced up at Mrs Matsuda.

“Oh, ignore him. He’s just excited to have guests for once that I’m feeding instead of eating,” Mrs Matsuda told him offhandedly, missing the way Tadashi suddenly choked on his tea. She glared at the side table and shook one bony finger at it. “Now get over here and bring me my tea, you stupid pile of lumber! I never should have picked you up from that auction, you were clearly the most shoddy piece of spellwork I’d ever seen! Hurry up or I’ll use you for firewood!”

The side table quickly complied.

“I-I’m sorry,” Tadashi coughed out, trying to clear the tea in his throat. “Did you say that you eat people?” He suddenly thought of Mochi’s comment about sending him to his death. He’d thought it was just a joke at the time, but now he wasn’t so sure.

The old woman eyed him for a moment before she suddenly burst out laughing. “Oh, caught that did you? Sorry, old joke, I suppose. I used to be quite the old hag, back in the day,” she told him with the air of someone letting him in on a grand secret, leaning in closer and stage-whispering. “They had a few different names for me back then. Onibaba, Old Hag, Wicked Witch, Baba Yaga. Oh, I’ve been called plenty of nasty things in my time. Of course, I might have deserved it a bit, what with the eating people and all. But I grew bored with it, so I decided to settle down somewhere nice and try just living for a bit. I must admit, your Aunt’s gingerbread was what convinced me that San Fransokyo was the place to stay. I haven’t had any that good since I left the old countries behind.”

She started humming to herself, as if recalling the taste of said gingerbread. Tadashi took the opportunity to place his sugar cookie back on the tray, suddenly uncertain about any of the food she offered.

“Oh, but enough about that. You can just call me Obaa-san,” she told him kindly with a gentle pat on his hand.

“Granny?” Tadashi clarified, slightly bewildered.

“But of course!” the old woman insisted. “Now drink your tea.”

Baffled and more than a little terrified, Tadashi did as he was told.

Mrs Matsuda fed him, and gave him a room to stay the night, though Tadashi wasn’t completely certain he could actually sleep anymore. It was still nice to have somewhere to just sit and be still for a while, which was almost the same thing he guessed. Thankfully the room she gave him was rather tame compared to the rest of the house, if a little bare. He sat down on the bed once she’d shut the door behind herself and just stared at his hands. He realized it was time to try coming to terms with everything that had happened to him in the past 24 hours, now that he had a moment to himself. There was a lot to think about.

Tadashi sat in the darkness of Mrs Matsuda’s spare bedroom and just concentrated on breathing for a while, feeling very lost and confused, and wishing desperately that he could go home. But every time he closed his eyes Hiro’s terrified face flashed through his mind, so Tadashi resolved to wait and see. He didn’t dare go home again until he got whatever these powers were under control.

Tomorrow, he resolved. Tomorrow he would talk to Mrs Matsuda about what had happened to him, and maybe she could help. He could only hope she would, and that he’d be home as soon as possible.

+++

He ended up staying at Mrs Matsuda’s house for a week. Although she had frightened him at first, Tadashi soon found that Mrs Matsuda just acted a lot scarier than she actually was. She left the house every day at her usual time to stop by the cafe, leaving Tadashi behind to watch the house (or rather the house watched _him_ , which wasn’t creepy _at all_ ), but once she returned she quickly filled up his time with all sorts of activities. She had him helping her making potions and casseroles, sweeping the porch and cleaning out the cauldron, catching the cockatrice and reshelving the spellbooks. She kept him busy, which he was grateful for, because it gave him less time to think and stew in his misery.

When she wasn’t having him complete various chores, she was teaching him things. He didn’t have much talent for magic, something she attributed to his status as a male more than anything, which he tried not to be insulted about, but he absolutely _loved_ when she started telling stories. She’d been alive for longer than he could possibly imagine, and so she always seemed to have some new story to tell that was so fantastical that if he wasn’t currently a ghost sitting in a witches’ house, he’d never have believed it. Some stories were terrifying, some funny, but no matter the story he soaked it up like a sponge.

On top of that, she gave him some advice for controlling his strange new powers.

“What you really need is a spirit medium to help you channel your energy, but most of the spirit mediums are gone now. It was a dying art even back in my heyday, and now? Ha!” The old woman spat into her mortar and pestle, grinding the saliva into the herbs she was currently working into a paste. “As far as I can tell, the last of the mediums died roughly a decade ago. Now it’s only the pretenders and those with a hint of talent left.”

“So if I can’t ask a medium for help,” Tadashi slowly pondered as he tossed a shrivelled lizard’s tail on top of the herbs to be crushed, “what else can I do?”

The old woman scrapped the paste out of her mortar and started transferring into a jar, murmuring chants under her breath into the container the whole time. Only after she had finished did she answer him. “Honestly? I have no idea. In all my years, I’ve never seen a ghost quite like you, especially not one so...’fresh’ as it is. Ghosts, yes. Fire starters? Of course! But a ghost with fire affinity? Not at all. My best guess, you powers seem to be connected to your emotions. Try not having any.”

His face fell. “Gee, thanks. I’ll get right on that,” he told her sarcastically. Mrs Matsuda cackled at him and flicked a bit of excess paste at him from her dirty pestle.

Thankfully she _did_ give him a bit more advice than just that. Meditation had never played a large part in any of her stories, but she’d travelled a lot, and she’d apparently been very close friends with a Greek Muse of meditation named Melete, and she’d learned a few tricks to pass on to him. Tadashi wasn’t sure if it was really helping or not, but at least he felt a little bit more calm about his situation. It helped him come to terms with what had happened.

But by the end of the week, Mrs Matsuda decided he’d overstayed his welcome, and unceremoniously pushed him out the door with a bag full of potions, a strange antique amulet and a set of freshly mended clothes. Tadashi was at a bit of a loss for what to do next, not sure if he was safe to go home yet or not, but to his pleasant surprise when he left Mrs Matsuda’s yard and walked far enough away that it looked like a regular house again, a familiar shape was waiting for him under the streetlamp on the corner.

“Mochi!” Tadashi called out in greeting, a genuinely pleased smile growing on his face. He still wasn’t completely certain how he felt about the nekomata that had been the family pet for years, but he at least knew it was nice to see such a familiar face.

“Ah, there you are!” Mochi said happily as Tadashi reached him. The cat started purring and winding himself around Tadashi’s legs, bumping his head against Tadashi’s knees almost hard enough to knock him over. Eventually Tadashi simply picked Mochi up into his arms and started scratching him behind the ears. He could feel the force of Mochi’s purs rumbling through his chest, and it was oddly soothing.

“Ahhh, that’s much better,” Mochi purred. “You wouldn’t _believe_ what it’s been like back home since you’ve been gone. I’ve tried my best to keep everyone’s spirits up, but they’ve been understandably...morose lately. Please tell me you’ve managed to figure out those powers of yours.”

“I...well, I think?” Tadashi finally said, although it was more of a question than a statement. “I mean, I haven’t set anything on fire accidentally lately, so...yeah. I’m not sure if that’ll be good enough though. Mrs Matsuda...sorry, Obaa-san, says that if I can control my emotions, it might help?”

Mochi eyed him for a moment, and then shrugged. “Eh, close enough. Sounds like you’ve at least got some control. And I trust you to recognize when you’re getting too worked up again. Now, let’s get you home.”

Tadashi was too relieved to disagree. Mochi was right, even if he wasn’t completely sure how to control his powers, at least he knew now that if he started getting upset he should just leave before he caused any damage. And honestly, he wanted to see Hiro and Aunt Cass again so badly that he was willing to risk it at least for a little bit. He just needed to know how they were doing.

The pair walked home together, Mochi leading for the most part. Now that it was daylight, and he had an experienced guide with him, the strange new changes to the city were a little less jarring to Tadashi. He stared in open wonder as they walked back into the city proper, trying to take in as many details as possible. A family of what he recognized as Tanuki chased each other across the power lines overhead, the eldest cursing and the youngest giggling. They walked past a person in a ragged hooded cloak manning a card table covered in glass lanterns with tiny fairies trapped inside for sale, though in a currency Tadashi wasn’t familiar with. A pair of fox-tailed women eyed him appraisingly as they approached until Mochi cleared his throat loudly. Then they merely walked away, giggling into their trailing kimono sleeves. At one point Mochi stopped to make conversation with a massive shaggy black dog with glowing red eyes, which frightened Tadashi at first until the dog’s tongue suddenly lolled out of its mouth and its tail started wagging like mad. It was hard to be afraid of the dog after that.

As they got closer to the cafe, he started seeing more mysterious shops pop up, like the mask shop from the night before. He now gazed into their window displays with curiosity rather than fear, and was left marvelling at their contents. One sold what looked like potion ingredients, another was selling strange-looking animals and tiny creatures. Yet another looked like it exclusively sold paper lanterns, though each of them was beautiful and covered in elaborate patterns and symbols that must have had some significance. Once they passed by the mask shop from before, their familiar faces blinking and smiling at him, Tadashi felt himself become more confident in his surroundings. He knew where he was now.

Sure enough, the Lucky Cat Cafe appeared before him not even five minutes later. He started for the front door on habit alone, when it suddenly swung open in front of him, emitting a very familiar figure.

“Baymax?” Tadashi blurted out, baffled by the sudden appearance of his project. In the whirlwind of the past few days, he’d forgotten he’d brought Baymax home before the showcase.

“What on earth is _that_?” Mochi asked, tilting his head and lashing his tails in confusion. It took Tadashi a moment to remember that he’d never activated Baymax at home, so the nekomata would never have seen the robot before.

“Uh, that’s Baymax, the robotics project I was working on before I...uh, before the fire happened,” he explained distractedly, starting to follow after Baymax and trying to see what the robot was holding in his hands. It looked sort of like a petri dish, but why would Baymax be wandering around with something like that? Why was he wandering around at all? Was he malfunctioning? Tadashi felt a brief flash of irritation at himself. Looked like he hadn’t quite perfected Baymax’s coding yet after all.

His irritation was very soon replaced with terror as he watched Baymax suddenly walk into traffic right in front of an oncoming car.

“Baymax!” he shouted, his hands flying up to grip his hair. Thankfully the driver of the car managed to slam on the breaks before he could hit Baymax, but it was still far too close. Baymax didn’t even look up from the object he was carrying, walking diligently along with a single-minded focus, right into the path of yet another vehicle. Once again, disaster was narrowly avoided, but only just.

“Oh man,” Tadashi moaned, preparing to run after his creation, when he heard the door of the Lucky Cat Cafe chime again. When he turned to look, he was momentarily caught off-guard at the sight of Hiro, standing on the sidewalk right in front of him. He hadn’t seen his little brother in far too long, and so he couldn’t help pausing a moment to just take in his appearance.

Hiro looked paler than Tadashi remembered. There were dark circles under his eyes, like he hadn’t been sleeping much. They were familiar from the days leading up to the showcase, where Hiro had often pulled all-nighters to put the finishing touches on his microbots, but they should have been gone by now. Instead if anything they looked deeper. His clothes and hair were also even messier than usual, as if he hadn’t bothered to take care of himself, and had just thrown on his outfit at random. Tadashi could feel himself choking up a bit at the signs of Hiro’s suffering, but a familiar flicker from his hitodama forced him to jolt himself out of his emotions before he could lose control.

Not that it mattered, because almost as soon as Hiro appeared, he bolted off, heading after Baymax like a hound after a rabbit. Well, a particularly spastic hound. The boy stumbled and flailed as he dodged into traffic, frantically chasing after the rogue robot and shouting after him at the top of his lungs, heedless of the stares he was getting from the people passing by.

The nekomata and the ghost stood on the sidewalk and watched Hiro running for a moment, wincing simultaneously as he tripped over the curb and nearly fell into a garbage can.

Tadashi sighed and dropped his face into his hands. Hiro was in trouble again. At least _some_ things didn’t change. “I...think I’m going to go after them,” Tadashi finally said after a moment as Hiro ran too quickly down the street and crashed into a lady doing a bit of window shopping.

“Might be best,” Mochi agreed, not taking his eyes off of Hiro. He winced again as Hiro stumbled yet again and nearly fell into traffic. “Better hurry.” 

Tadashi caught up to Hiro quickly, as he could simply pass through obstacles rather than having to go around them. He winced and sighed and hissed every time Hiro stumbled or tripped or ran into something, and privately moaned to himself that he couldn’t actually catch Hiro before he collided with anything. All he could do was watch and hope Hiro didn’t end up tripping and breaking his neck. If Hiro ended up in the afterlife with him _this soon_ , Tadashi would kill him.

At one point the brothers spotted Baymax’s back from the other side of a large crowd, and they both immediately started charging after him. It wasn’t until Tadashi had caught up to his robot and found himself alone that he realized that Hiro was stuck on the other side of a large crowd of people that Tadashi had just walked through. He groaned and smacked himself on the forehead, before running back to Hiro’s side

Tadashi was so distracted looking for Hiro that he didn’t see the way Baymax briefly turned towards him, blinking his eye-like cameras.

The brothers continued to follow after Baymax, this time Tadashi keeping a closer eye on Hiro to make sure he didn’t lose him, moving deeper and deeper into the less travelled parts of the city. As they ran, Tadashi noticed that the paranormal side of the city was also changing to match the new surroundings. There were fewer cheerful colours and friendly-looking faces, more hooded cloaks and glowing eyes. He pressed himself closer to Hiro’s side, almost close enough to touch, and watched these new creatures warily, his hitodama flaring up a bit larger than usual in warning. Thankfully none of the shady figures came any closer, and the two were able to catch up to Baymax unscathed. Still, Tadashi kept his hitodama close, glad that for once they were helping instead of causing him problems. It was about time they were useful.

He noticed then that Baymax had finally come to a stop, and he hurried after his brother over to his robot’s side.

+++

They’d stopped in front of an abandoned warehouse. Somehow, Tadashi was not thrilled with this latest development.

He only became less thrilled the further they went into the warehouse. It was bad enough watching Hiro nearly break his neck sneaking in through the window, but when Hiro started approaching a mysterious glow coming from around the corner Tadashi could feel himself break out into a cold sweat. He did _not_ like this at all, especially because he couldn’t do anything to stop this. His only hope was that Baymax would catch up to Hiro soon and talk him out of exploring any further.

However, after a brief pause where Baymax almost got to test out his defibrillator palms, and Tadashi was momentarily pleased to see they seemed to be working, his hopes were dashed when a massive wave of darkness suddenly rose up behind them, the tendrils twisting into threatening shapes and somehow letting out a frightening hissing sound that almost sounded like voices. Tiny glints of metal within the shadows caught Tadashi and Hiro’s attention, and they were both horrified to recognize Hiro’s microbots embedded into the dark mass, which was slowly curling closer.

“Oh no,” Baymax said, summing up what Tadashi was feeling almost perfectly, although with much less swearing.

The shadows surged forward, and Hiro and Tadashi bolted.

They’d barely taken three steps when Hiro seemed to realize that Baymax wasn’t right behind them and skidded to a stop. Tadashi barely managed to do the same, swearing when Hiro darted back for his robot.

“Oh god, just leave him, Hiro!” Tadashi shouted, even if Hiro couldn’t hear him. “It’s okay, I have backup files, he’s not worth you dying too!”

Of course, Hiro ignored Tadashi, not even aware of his presence, instead pulling the balloon-like robot by the arm. The pair reached where Tadashi was waiting for them and rushed past, Tadashi hurrying to follow. As they ran he glanced back to see how close the shadows were, and yelped as a leading tendril lashed out and struck him across the face, leaving a burning welt right beneath his eye. These shadows could hurt him, even though he was already dead? And there, behind the shadows, Tadashi caught sight of their source. There was a figure standing on the other side of the warehouse floor, the twisting shadows seeming to emanate from his feet. He was wearing a Kabuki mask, the red and black lines stark against the white porcelain, but Tadashi could still somehow tell that whatever the man was, he wasn’t human. If anything, he seemed slightly familiar, almost similar to Tadashi himself but...darker. Twisted. Warped. And floating behind the figure’s head was a single hitodama, though its deep purple flame was weak and looked to be on the verge of guttering out. With a sudden jolt of recognition from Mrs Matsuda’s stories and his mother’s book, he knew exactly what he was looking at.

“Onryo,” Tadashi whispered to himself. A vengeful ghost known for hunting down and harming the living. A much more dangerous kind of Yurei than Tadashi himself.

Terrified now, both for himself and his brother, he doubled his pace, chasing after Baymax and Hiro as they tried to escape the warehouse and the Onryo’s shadows. By now Hiro had managed to find a mostly intact metallic staircase leading up to the catwalks hanging over the warehouse floor, and was pushing Baymax up it as fast as he could avoiding the spots where the stairs were missing. Tadashi quickly followed, looking back over his shoulder every few seconds to see how close the shadows had gotten. He nearly screamed when he saw them practically snapping at his heels, some of the tendrils surging over their heads and reaching out for Hiro like claws. In a fit of panic, Tadashi reached out with all his strength to shove Hiro out of the way, even though he knew his hand would pass right through.

Except he didn’t.

There was a moment of absolute confusion where Tadashi wasn’t sure who or where he was, or even which way was up. Then, he found himself blinking up at the warehouse ceiling with his hitodama circling overhead, gasping for breath and feeling like his heart was going to pound out of his chest, except that didn’t make sense because he was _dead_ , he _didn’t have a heartbeat_!

There wasn’t time to ponder that though, because almost as soon as he came back to awareness, the hissing shadows reappeared above his head. He let out a startled yelp that sounded far higher than it should, and rolled to his feet, his eyes immediately seeking out Baymax’s bright form in the darkness. He reached out for his robot’s hand and grasped it, starting to pull. Only then did he notice the difference.

His hand was _way_ smaller and smoother than it should have been. And instead of the green blazer he’d been wearing before he’d...during the showcase, he was somehow wearing Hiro’s blue hoodie? And how was Baymax suddenly _that much taller_ than him?

He didn’t have much time to think about it though, because at that moment the shadows came down on them like a rain of spikes. Tadashi practically threw himself to the side, dragging Baymax in his wake, and the shadows crashed down on the catwalk where they’d been mere seconds before with a metallic shriek. Tadashi scrambled to his feet, frantically glancing around for Hiro, even though something told him he already knew exactly where Hiro was. His suspicions were increased when he found no sign of his little brother anywhere nearby. Only Baymax was there, blinking down at him in confusion from his sudden height advantage.

A glance down at himself confirmed his fears, as he took in the scrawny body dressed in loose clothing that he’d recognize anywhere. He was somehow _inside_ Hiro’s body, controlling it.

Oh god, he was possessing his brother!

The hissing sound of the shadows suddenly getting louder reminded Tadashi that he didn’t have time to freak out about this. His eyes darted this way and that, looking for a way out, when he spotted the open window Baymax and Hiro had snuck in through earlier. He started running for it desperately, tugging Baymax along as best he could. When they reached it, he shoved the robot forward, trying to push him through the tiny opening, only for Baymax to get stuck. He swore in frustration and pushed harder, all the while aware of the shadows regrouping behind them, but he wasn’t having much success. Hiro was just so much smaller than him, and unfortunately weaker. He found himself wishing very dearly for his own body.

Gathering all of the strength in Hiro’s smaller body as he could manage, he gave one final shove. Fortunately, the window gave a little, allowing him to flip around and finally get outside the warehouse. _Un_ fortunately Baymax was still stuck, and now Tadashi was clinging to his leg and dangling out of a third storey window in his brother’s body over the hard concrete below. He screamed and dug his fingers into Baymax’s soft vinyl, feeling his grip slowly slipping.

Just at that moment, something impacted with Baymax hard enough to knock him loose, and once again Tadashi was sent flipping through the air. He had a moment to think that Hiro _would_ be joining him in the afterlife soon, and it was all his fault, when suddenly he felt soft inflated arms circling around his middle. Baymax had managed to grab him in midair and was tucking Hiro’s body close against his soft center, ready to break his fall. In that moment Tadashi could not have been more happy with his invention.

Then they were impacting against the ground and Tadashi lost track of things again. When he came to, he found himself back to normal outside of Hiro’s body, blinking in confusion. The fall must have knocked him free, though he honestly had no idea how. He quickly checked on Hiro, who was groggily rising to his feet with the help of a diligent Baymax.

“Ugh...Baymax?” Hiro groaned, shaking his head woozily. “What happened? How did we get out here?”

“We jumped out of the window,” Baymax answered him honestly.

“We did?” Hiro looked up at the window far overhead. Tadashi looked up as well, nervously checking for any signs of the shadows, but so far it seemed that they weren’t being followed.

“Yes. Hiro, your electrolyte balance temporarily became very erratic while we were inside the structure. Though they have returned to their normal, I would suggest that you rehydrate yourself to prevent further imbalances.”

“Yeah, yeah, whatever,” Hiro said distractedly, “I’ll get right on that. But seriously, did you see that? The way the shadows just...attacked us? And those were my microbots!”

“I did observe that phenomenon,” Baymax agreed.

“Oh man, Baymax, whoever the heck that guy was, he stole my microbots!” Hiro shouted, tugging at his hair in frustration, “and did something _weird_ to them! What do I do? Oh man, what do I _do?_ ”

Tadashi wanted to tell Hiro that _running for his life_ was what he should be doing right now. Thankfully at that moment Baymax piped up, suggesting that if his personal belongings were stolen, they should report it to the authorities. Hiro, to Tadashi’s shock and relief, listened. Feeling very exhausted all of the sudden, Tadashi trailed after them, glancing over his shoulder every few minutes to make sure they weren’t being followed.

As they headed back into the livelier parts of the city, if Tadashi even started to suspect one of the supernatural creatures or figures would try to approach his brother he sent his nastiest glare in their direction and flared up his hitodama. He was not in the mood to watch his little brother get attacked by something inhuman again today. Thankfully the monsters and creatures kept their distance. For once Tadashi was the scariest thing on the street.

+++

Tadashi left Hiro at the police station. He figured his brother would be safe enough there, and besides, there had been a pair of rather intimidatingly large rock golems covered in glowing blue sigils standing guard outside. They were each wearing a police officer’s hat that looked comically small on their huge boulder-like heads, but their glowing eyes stared straight down at him as he had approached behind Hiro and Baymax, and Tadashi had quickly lost his nerve. Instead, he’d headed back into the city, back towards the warehouse they’d just run from. He had some things to look into.

It didn’t take him long to find his way back. Despite their distraction chasing after Baymax on the way there and the terrified flight away from it on the way back, he distinctly remembered the area. Soon enough he was standing outside of the warehouse, his breath hitching slightly with nerves, but his hands clenched in determination. His brother had been attacked by a ghost who’d stolen his microbots, he needed to get those microbots back and make sure the ghost didn’t come near his family again. Also, there was something familiar about the ghost, but Tadashi just couldn’t figure out what it was. Hopefully he’d find his answers soon.

With one more deep breath for strength, Tadashi phased through the wall of the warehouse as silent as a cat, reappearing on the other side deep in the shadows behind a stack of dusty crates and abandoned equipment. He paused a moment to adjust to his new surroundings, and then carefully peeked out from behind his cover. His ears perked up when he heard the groaning of moving metal, and a clang, like something heavy had been dropped.

Curiosity now overwhelming his fear, Tadashi started to sneak forward, creeping along the warehouse floor and ducking behind any and all cover he could find. As he came closer to the center of the warehouse, he suddenly realized that his hitodama were still floating happily above his head and shoulders, shining brightly like beacons. Groaning, he glared at them, trying to figure out if he could somehow will them to become dimmer, or at least hide behind him or something, but after a few moments of waving his arms at them and scrunching his face up in concentration, they were still floating there, just as cheerful and bright as ever. With a sigh, he gave up, and just did his best to keep himself as hidden as possible.

He finally turned around the last corner before the wide open space of the warehouse, and his eyes went wide as he saw what lay beyond. The shadows were still there, hissing and lashing out at nothing, but the bulk of them had curled around the feet of the Onryo like a loyal dog. Even from his current position, he could catch the glints of his brother’s microbots embedded in the shadows like dark gemstones. Tadashi’s heart sank as he realized that it might not be as easy as he’d hoped to recover his brother’s invention, especially if those shadows could still hurt him like they had earlier.

Just then he noticed a third section of the shadows that had split off and seemed to be moving something. As they passed through the weak sunbeams that managed to pour through the holes in the warehouse roof, he saw them carrying what looked like the components of a 3d printer, as well as plenty of welding equipment and other heavy machinery Tadashi couldn’t identify. The shadows brought them forth and presented them to the Onryo, who barely glanced back at them with a nod of his head.

So the shadows answered to the Onryo? Perhaps they were even a part of him, Tadashi theorized. But what would a vengeance ghost need with all of this equipment?

It looked like Tadashi was going to find out, because just at that moment one of his hitodama floated a bit further out than usual, and came out into the open. Immediately the shadows sprung up like snakes, hissing and whispering loudly, tendrils forming pointed tips like spears. The Onryo looked over as well, his golden eyes flashing threateningly in the dim light of his single hitodama.

Well, there was no point in hiding now, Tadashi figured, so he stepped out from behind his hiding place. The shadows shifted to face him, but didn’t move any closer, which Tadashi was silently thankful for. They were terrifying enough as it was.

“H-hello,” Tadashi greeted the other spirit, cursing as his voice cracked a little. He cleared his throat, and tried again.

“Hello, sir,” he started respectfully. No point in getting aggressive just yet, especially as the other ghost wasn’t attacking him at the moment. Maybe this Onryo was much more reasonable than Tadashi originally thought. Maybe he and Hiro had just arrived at a bad time. After all, he couldn’t even be certain that the spirit even _had_ stolen the microbots. And it wasn’t like Tadashi would be able to reclaim them on his own, not unless he wanted to physically pick all of the microbots out of the shadows by hand, one by one. But the ghost seemed to control the shadows, maybe he could command them to let the microbots go. The least Tadashi could do was _try_ to be polite and ask nicely before he assumed the worst.

“I’m sorry to trouble you, sir, but your shadows seem to have taken something that belongs to my brother, and I’d like to have them back, if you don’t mind,” Tadashi explained.

The Onryo didn’t move, still watching him silently. Maybe he didn’t understand what Tadashi was talking about?

“Uh, those things,” Tadashi clarified, pointing at one of the tiny glimmers in the shadows. The Onryo’s mask covered up his eyes, so Tadashi couldn’t tell if the spirit looked or not, but he thought he saw the Onryo’s head move a little. Still the Onryo was silent.

“Please?” Tadashi tried one more time. The Onryo’s head tilted slightly to the side.

Getting annoyed now, Tadashi let out a great sigh. “Look, I’m new at this whole ‘dead’ thing, but I’m pretty sure you can’t kill me again. So please, just give me the microbots back, and I will leave you alone and never bother you again. Otherwise I’ll just have to haunt you until you go nuts. I think I can do that. Ghosts haunt things, right?”

 _That_ caught the Onryo’s attention, though judging by his dark chuckling it wasn’t in a good way. Tadashi stood there nervously, wringing his hands and suddenly really wishing he had his hat back. He usually fiddled with it when he was nervous and right now he missed its presence terribly. The Onryo’s laughter was not pleasant, sending a shudder down Tadashi’s spine, though he still couldn’t shake the feeling of familiarity it gave him too. It was like he’d heard the spirit’s voice before, and it was just being warped by the mask, but how was that possible? Tadashi also couldn’t help but notice the way the Onryo’s lone hitodama had started flaring up, and his own hitodama burned brighter in response.

The Onryo’s laughter suddenly cut off, and they were once again left facing each other in silence, aside from the ever-present whispers of the shadows.

“So...is that a yes?” Tadashi asked hopefully, even though he was pretty sure the answer was the opposite.

“Heh,” the Onryo chuckled darkly. Then he threw out his hand, his palm facing towards Tadashi.

The shadows surged.

Tadashi didn’t even have time to scream before he was overcome. The shadows were _everywhere_ , surrounding his arms and legs and chest, tugging at his hair, even pushing into his mouth to choke him. He tried to scream, but couldn’t make any noise past the suffocating darkness. It was everywhere, surrounding him, _consuming_ him, burning and freezing at the same time. He could feel them reaching down, _down_ , somewhere inside of him, somewhere private and secret, searching for something. He tried to scream again, tried to fight back, tried to do _anything_.

All of the sudden the shadows were gone, and Tadashi was left curled up in a ball on the warehouse floor, shaking and fighting back the urge to sob. He’d never felt so helpless and overwhelmed in his life, even when he’d died. He felt violated. His hitodama were burning so low he almost couldn’t see them, even as they floated protectively near his face.

The shadows were gone, but the Onryo was standing over him. Tadashi scrambled to his feet, reluctant to let the creature near him again, but the Onryo merely grabbed him by the arm and jerked him close. Tadashi shouted and lashed out, trying to break free, but it was like fighting a brick wall. The Onryo seemed to barely even notice his efforts, his grip like steel.

Despite his struggles, the Onryo pulled him close, leaning against the side of his head so close Tadashi could feel the cool porcelain of the kabuki mask against his skin.

“Stay out of my way, _boy_ ,” the Onryo hissed in his ear, “Or I’ll make you _wish_ you could die again.”

And then in a whirl of shadows, the Onryo was gone, leaving Tadashi sitting there in the middle of an abandoned warehouse shaking and alone, and absolutely terrified.

**Notes for the Chapter:**

> Thank you to everyone for your wonderful comments! We've read and flailed over them all, and we're so happy to hear you're enjoying the story so far!
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	4. Practice

It had taken the better part of the rest of the day for Tadashi to gather himself up and walk home. He was so jumpy by then that when a friendly-looking cyclops oni walked up to him and asked him if he was okay, he immediately bolted, ducking through the crowds, heedless of the chaos he was causing. He didn’t stop until he was sure he’d lost anyone who might be following him, and only then realized that he’d overshot the street that led him home and that he needed to double back about three blocks or so. A passing faun with flowers for hair leading a group of children that glowed like coals tried to offer him directions, but Tadashi’s hitodama suddenly flared up with his fear, causing a nearby pile of garbage to burst into flames. Rather than deal with the mess, Tadashi ran again, leaving the faun cursing after him while the glowing coal children happily jumped into the flames and danced around.

By the time he arrived at home, it was almost nighttime, and he could see Aunt Cass switching the sign on the cafe door from open to closed. He felt a pang in his heart at the sight of her. He hadn’t seen her since his accident at the wake, and he could immediately spot the changes his death had wrought on her. There were dark circles under her eyes that even her heaviest make-up couldn’t hide, and her clothes and hair were not up to her usual standards of neatness. She also looked like she’d lost a bit of weight already. Still, there was a smile on her face, even if it wasn’t as big and bright as he was used to, and Tadashi had to remember that this wasn’t the first time his beloved Aunt had dealt with a loss of family. His heart went out to her, but he knew she was strong.

Besides, between Aunt Cass and Hiro, Tadashi knew who really needed his attention at this point, and so he headed towards the garage instead of into the cafe. He could see the light beneath the large metal door, and knew Hiro must be working on something inside, though on what he had no idea. Maybe Hiro was trying to make more microbots to compensate for the ones that had been stolen. Tadashi phased through the wall again, prepared to find Hiro bent over a desk with his face screwed up in concentration as he worked on the tiny components of his invention.

Only Hiro wasn’t at his desk, and he wasn’t working on microbots. Tadashi was momentarily stunned when he realized the bulky armoured person standing in the middle of their garage lab wasn’t in fact a sumo wrestler, but _Baymax_. In carbon-fibre armour. _What_.

“Yeah! Fist bump!” Hiro announced, practically bouncing around Baymax like an excited puppy.

Baymax simply blinked in confusion. “‘Fistbump’ is not in my fighting database.”

Hiro shook his head and tried to explain what a fist bump was to the nurse robot, but Tadashi was too busy taking in Hiro’s work to really pay attention. The armour was relatively well made, despite the fact that Tadashi knew that carbon fibre wasn’t Hiro’s favourite material to work with. The joints were reinforced, and everything seemed to fit well together, though as he hadn’t really given Baymax knees, the leg armour looked like it lacked mobility. At first, Tadashi thought that maybe Hiro had put armour on Baymax to protect his invention, but then he spotted the scraps of broken plywood spread out everywhere.

All over the garage, any and all pieces of furniture or junk they’d collected over the years were lying on the ground, smashed to pieces. A couple of cinder blocks had been set up side by side just like they would be for a martial arts demonstration, with a splintered board lying between them. A glance at Hiro’s computer screen showed several martial arts videos cued, and a motion capture of Baymax frozen in the same position as the man in the video, in the middle of a high kick.

Oh god. His brother had turned Baymax into a giant battle bot.

Tadashi was gonna kill him.

But before he could give in to the urge to strangle his little brother, Hiro was already bouncing over to Baymax and jabbing his elbow into the robot’s side. “Alright, let’s go get this guy,” he told Baymax.

Only Baymax wasn’t listening. He was looking over across the room, blinking slightly. Tadashi followed his gaze, noticing the computer terminal he was standing next to was making strange noises, and the screen was glitching. Confused and more than a little annoyed that of course it was _his_ computer that Hiro had apparently managed to break, he leaned closer to inspect the screen, wondering what was making it fritz out like that.

Just as he reached out to touch the keyboard, the entire computer suddenly let out a high pitched whine and then sputtered and died. Meanwhile, the computer screen went dark in a shower of sparks.

Tadashi jerked back, just as Hiro ran over. “Aww, man!” Hiro whined. “What the heck? No!” He dropped down under the desk with a string of curses that he sure hadn’t learned from Tadashi, and started fidgeting with the wires, trying to figure out what had gone wrong. Judging by the increasing volume of swearing, it wasn’t going well.

Tadashi had moved away from the computer, startled by the sparks, but that had brought him closer to the vending machine full of snacks they’d installed in the garage shortly after turning it into a lab space. When he came too close, it also started to make worrying sounds and spark a bit, though not nearly as badly as the computer had. With a jolt, Tadashi suddenly remembered the old myths about ghosts and how they could mess with electronics. It looked like those myths were true. Very carefully he made his way to the center of the room, doing his best to avoid getting too close to any of the machinery they had lying around the lab space.

It wasn’t until he’d started checking around himself for any more equipment that he might mess with that he noticed Baymax watching him. Or at least, that’s what it looked like. Except he was a ghost, completely invisible to the living world, there was no way the robot could see him.

But when he took a deliberate step to the side, Baymax’s head turned to follow. When he stepped back, Baymax’s head returned to center. And when he jumped up and down, Baymax bobbed along. It was impossible, there was _no way_ Baymax should have been able to see him, but somehow he was following Tadashi’s every move.

“Unbelievable,” Tadashi whispered to himself.

Just then, Hiro crawled out from beneath the desk, grumbling under his breath. He had a handful of wires and a smudge of soot on his cheek. “Stupid fan blew, I’m gonna have to replace that later,” he grumbled. With an irritated motion he tossed the wires over his shoulder into a bin of spare parts before striding back over to Baymax. “But that can wait. For now, we’ve got a bad guy to catch. I’m not going to let him get away with what he did.”

At once, Tadashi knew who Hiro was talking about. The Onryo.

His entire body went numb with fear as the feeling of shadows crawling all over his body and choking him shot through him. The experience had been bad enough, feeling like dying all over again, but he was already dead and couldn’t be killed again. Who knew what would happen if those shadows got a hold of Hiro. He _couldn’t_ let Hiro go near the Onryo, he just _couldn’t_. 

“No!” he shouted, even though Hiro couldn’t hear him, instinctively reaching out to grab at Hiro’s shoulders. “Please, Hiro, no! You don’t know what he is! You don’t know what he’ll _do_ to you!” Once again, his hands passed right through, catching on nothing, but Tadashi couldn’t give up. He kept trying, grasping at Hiro’s shoulders, hair, hoodie, anything and everything he could reach, anything that could stop Hiro from going.

Oddly enough, Hiro twitched, rolling his shoulders like he could almost feel Tadashi’s touch, but he still didn’t stop.

“Come on, Baymax,” Hiro opened the garage door and gestured the robot forward. Baymax glanced back at Tadashi one more time, before starting to follow after the younger Hamada.

“No, please, _no!_ ” Tadashi screamed, frantic now. In desperation, he dashed around in front of them, holding out his arms like he could somehow physically block Hiro from leaving. His brother walked on obliviously, headed straight for him, and Tadashi reached out to push him back with all his strength.

The world flipped again. Up was down and down was up and he wasn’t sure where he was or who he was and there was blurs of colours and lights whirling around his head like a galaxy until suddenly the world righted itself and he was Tadashi Hamada again. Only he was facing the opposite direction he had been before. And the world had somehow gotten a lot taller.

A quick glance back _up_ at Baymax confirmed his suspicions. He had somehow taken over Hiro’s body again.

He stood there for a moment, trapped in indecision. On the one hand, Hiro couldn’t run off to confront the Onryo when Tadashi was controlling his body, so he would be safe, but on the other hand _Tadashi was controlling his body!_

“Oh man! Oh man, oh man, oh man. Not _again_! How did I? How do I? Oh god, what did I do?” Tadashi’s hands instinctively flew to his head. He’d previously had a habit playing with his ever-present hat whenever he was very excited or upset, exactly like he was right now. If he wasn’t wearing his hat, he’d grab at his hair instead. Except this time instead of familiar fabric or short spiky hair he was expecting, his fingers sank into Hiro’s much thicker and longer locks. Already on the border of a total meltdown after the stress of seeing Baymax in armour, Hiro attempting to find the Onryo, and accidentally possessing his brother again, this was the tipping point.

There was a flash of heat and light, and suddenly the couch that they’d left in the lab for those long nights of work burst into flames.

There was a moment where Tadashi could do nothing but stare at the bright flickering flames slowly consuming the ratty old furniture. His mind had gone blank with fear. It reminded him much too strongly of the fire at the showcase hall, the fire that had taken his life and turned him into _this_ , and the raw terror had consumed him. His vision was filled with nothing but fire, his lungs choking on thick black smoke and the smell of burning wood and fabric. Someone was screaming somewhere, sounding so painfully familiar, but the sound was muffled, like someone had shoved cotton into his ears.

He didn’t know how long he had been standing there, staring. But suddenly there were thick armoured arms around him, pulling him away from the couch. A massive round form stepped in front of him, blocking his view of the fire, and suddenly Tadashi realized it was Hiro’s voice he heard screaming like that. Except it was him. He was screaming in fear with Hiro’s stolen voice in Hiro’s stolen body. He cut himself off, but his breathing was still erratic and out of control. He could see his vision getting fuzzy around the edges, like he was about to pass out, and he couldn’t help but hysterically wonder what would happen if he fainted while in Hiro’s body. Would Hiro wake up with Tadashi still trapped inside? Would it be enough to jolt him out? What if it somehow hurt Hiro?

These thoughts were not helping him get his breathing under control, he thought angrily, but he couldn’t seem to stop himself.

Just then, the figure in front of him reached out and pulled him into a tight but soft hug. Tadashi stiffened for a moment, but then finally recognized who was with him. It was Baymax, who had removed most of his body armour, and was now slowly moving Tadashi away from the couch to the far corner of the lab. He was also talking to Tadashi in his normal soothing tone, though it was only just now starting to get through Tadashi’s panic.

“...as well as difficulty breathing. Diagnosis: panic attack. Treatments include cognitive behavioural therapies, medication, and breathing exercises. I shall guide you through one of these now,” Baymax instructed, the screen on his chest lighting up and displaying a helpful diagram on what to do. “Please follow along with the instructions you see on the screen.”

Tadashi did just that, taking deep breaths and holding them as Baymax displayed a helpful timer along with the diagrams. After a few minutes, he felt himself calm down, though he couldn’t help but still be a little concerned about the couch. Most of their stuff in the garage had been fireproofed after one too many experiments gone wrong in their youth, but it was still a sizeable blaze.

“Okay. Okay,” Tadashi took one more deep breath, and felt his shoulders drop. “Thanks, Baymax, I think I’m okay now.”

“I am happy to hear you feel better. Please let me know if you feel any of your symptoms returning.”

“I will, bud. Thanks,” Tadashi reached up as far as Hiro’s scrawny arms could reach and patted Baymax thankfully on the arm.

“You have been a good boy, Tadashi,” Baymax told him. “Have a lollipop.”

Tadashi chuckled and took the offered sweet, although he only tucked it into Hiro’s hoodie pocket rather than open it. Lollipops were more Hiro’s thing, something Tadashi had coded into Baymax’s design more as a joke than anything. He figured his brother would get a kick out of it, if nothing else. Besides, this wasn’t the time for candy. Now that he was calmer, he needed to find the fire extinguisher and put out the couch before it set of the fire alarm upstairs in the cafe. Aunt Cass would throw a fit if that happened. Tadashi started rummaging around the edges of the lab space, looking for the elusive red canister. Now where the heck did they put it after last time? 

And then what Baymax had just said registered in Tadashi’s mind, and all thoughts of fire extinguishers was forgotten.

“Wait, _what_ did you just call me?” Tadashi whirled around to face his invention. The nursing robot tilted his head and blinked.

“Tadashi,” Baymax repeated. “Is this not what you would like to be called? Would you prefer the more formal Mr. Hamada, or Hamada-san?”

Utterly shocked, Tadashi could only shake his head. “No, no, Tadashi is fine. It’s just...how did you know it was me?”

Baymax’s finger rose in his typical diagnostic explanation pose. “I have detected a recurring electrical anomaly in my circuits for which there was no identifiable cause. I have found on two occasions now that this usually occurs shortly before the behaviour, speech, and mannerisms of my patient Hiro Hamada change and become identical to those found in my creator, Tadashi Hamada. My research into loss and grieving has identified the concept of ‘life after death’ to me, and further research suggests that one possible theorized outcome is to become a spirit or ghost, which are suspected to cause electrical anomalies with their presence. I have thus concluded that you are the ghost of my creator, Tadashi Hamada. Is this not correct?” Baymax asked with another tilt of his head.

Tadashi’s jaw had dropped open and he stared at his robot. After a moment, he realized Baymax was expecting a response, and he quickly shook his head to clear it. “No, that’s...that’s exactly it. You’re right, I’m...I’m Tadashi. I just can’t believe you figured that out on your own.”

“Caring for Hiro has already caused me to learn and go beyond your original programming, as he is a most complex patient. I do not know if I will be the best health care companion for him, though he has already helped me improve by teaching me karate.”

“I know, _believe me_ , I know.” Tadashi told him ruefully, thoroughly impressed with his creation at the moment. He’d poured his heart and soul into Baymax’s coding, and he’d made sure that the AI could learn to better keep up with the ever-evolving medical field, but he hadn’t realized that Baymax’s programming would be able to make such leaps of deduction. He was kind of proud of his robot. Especially if he was trying to keep up with Hiro.

“Hiro can be a handful. But you’re doing your best buddy, and that’s all I can ask of you. I’m trying to keep an eye on him too, though if it’s affecting your circuits, maybe I should stay away.”

“I am not affected to any degree that will compromise my programming.”

“That’s good to hear,” Tadashi said in relief. Just then the burning couch let out a particularly loud crackle, reminding Tadashi that it was still burning away. “Oh crap!” Tadashi yelped, “Baymax, can you find the fire extinguisher anywhere?”

“I believe it was used as a target when testing out my new karate programming,” the robot confessed.

Tadashi cursed, looking around for another solution. It was a testament to how well they’d fireproofed the lab that nothing else had caught yet, though he was a bit concerned no smoke detectors had gone off. He looked around frantically for something to put out the blaze, but other than Hiro’s half-finished soda on the computer desk nothing immediately presented itself.

“Come on, Hamada, _think!_ ,” Tadashi hissed to himself, face scrunched up in concentration. Just then, one of his hitodama floated past in front of his face, and he got an idea. “That’s right. If my powers can _start_ a fire, maybe they can put it out! That makes sense, right?” He looked back at Baymax, who merely blinked at him. No help there, of course.

“But how?” he whined out loud to himself, racking his brains for an idea. He tried thinking back to Mrs Matsuda’s teachings. She’d said his powers were connected to his emotions, right? And being upset had started the fire. So if he was calm, then...maybe that would help. He tried taking a few deep breaths, focusing on the feeling of being alive, even if it was borrowed life. He focused on Hiro.

A feeling of cool power rushed through him, making him feel strong. He could do this, somehow he just knew it. He could feel the blood rushing in Hiro’s veins, feel the air in his lungs. His little brother was with him, strengthening him even if he didn’t know it. With Hiro’s help, Tadashi felt he could do anything.Taking a calming breath, he reached out and gestured towards the couch, focusing on the heat and fire with all of his senses. He thought of the feeling of it, the warmth and light, and tried to hold it in his mind. Then, he slowly lowered his hands, imagining the flames lowering along with it.

Tadashi couldn’t see it, but for a moment Hiro’s normally brown eyes flashed brilliant gold and blue, matching the flames of Tadashi’s hitodama.

It was almost effortless to smother the flames, and Tadashi surprised himself with a burst of laughter. He felt _powerful_ , in control, like he actually knew what he was doing for the first time since he ran into that burning building. It was a wonderful change of pace, and he revelled in the feeling. 

When the couch was put out, it was completely ruined, the fabric turned to ashes and the frame no more than a charred husk, but aside from the still slightly smoking remains of the couch there was no sign that there had ever been a fire at all. Tadashi looked down at his - Hiro’s - hands in wonder. _He’d_ done that.

“Wow,” he whispered to himself. After a moment he looked up at Baymax, who had been silently watching all the while. The robot blinked at him, and although he had no mouth, Tadashi could have sworn he was smiling.

It faintly occurred to Tadashi in that moment that if possessing Hiro gave him such a boost in control and power, perhaps the Onryo was possessing someone too. Maybe that’s where his overwhelming strength had come from. If Tadashi’s theory was true, then maybe, if he was possessing Hiro, just maybe he could actually match the Onryo’s power, instead of being completely overpowered like last time.

He discarded the thought almost as soon as it formed. Even if he _could_ win, he would never put Hiro at risk like that. The fact that he’d even considered it, as brief as it had been, left him feeling slightly sick. No, he still wanted to keep Hiro as far away from that monster as possible.

To further remove the temptation, Tadashi decided he needed to get out of Hiro’s body ASAP. But how was he going to do that? Last time it had taken a fall out of a third storey window and bouncing off of Baymax’s belly, and he wasn’t interested in repeating that experience. But he couldn’t seem to will himself out, as much as he furrowed his brow in concentration, and jumping around only seemed to be tiring him out.

He even asked Baymax for suggestions, but the robot of course had nothing.

Just as Tadashi was about to tear Hiro’s hair out in frustration, he heard a very familiar purring sound coming from outside the garage.

“Oh hoh hoh!” Mochi chuckled as he sauntered into the lab space, taking in Tadashi-in-Hiro, the half-armoured Baymax, and the blackened and smoking remains of the couch in one sweeping glance. He tisked and shook his head, before strolling up to the computer desk. He quickly hopped up onto the rolling chair and then to the desk itself, settling himself gracefully and curling his twin tails around his paws. “What have we here?” the nekomata asked, the markings over his eye mimicking raised eyebrow.

Tadashi glanced around, seeing the mess around them, and ducked his head sheepishly, rubbing at the back of his neck. “Heh, oops?” Tadashi said.

“Hello, Hairy Baby,” Baymax greeted with his usual circular wave, before waddling forward with his arms outstretched. A moment later Mochi was sitting in Baymax’s arms, purring like mad while the robot stroked the top of his head.

“I must say, Tadashi, this is clearly your best invention yet. A soft cat bed that also administers pets, absolute genius!” Mochi praised, eyes closed in happy bliss. Tadashi opened his mouth to correct the cat, but then thought better of it. At the moment, that was a pretty accurate description of Baymax.

He didn’t bother asking how Mochi knew it was him. The cat could possibly see him inside Hiro somehow, and if he couldn’t he could probably see the hitodama.

That’s when Tadashi remembered, Mochi was a nekomata. They were supposed to be associated with the dead and all that, and Mochi seemed to know a lot about ghosts and supernatural things. Maybe he knew how to unpossess someone!

Mochi’s one eye opened slightly when Tadashi asked him about it. “Hmmm? Are you stuck or something?”

Tadashi’s shoulders slumped in embarrassment. “Yeah.”

The cat grinned at him.

+++

Mochi was a wonderful pet, always ready to curl up in your lap or at your side whenever you needed a bit of company, but he was an absolutely _horrible_ teacher. It didn’t help that he kept referring to different parts of Tadashi-in-Hiro’s body as ‘paws’ or ‘the muzzle’, and he kept getting distracted whenever Baymax started petting a particularly nice spot. It left Tadashi more than a little annoyed. He made a mental note to pull a poltergeist and ‘accidentally’ knock the family’s stash of catnip out of the highest shelf the next time Mochi was nearby. Let’s see how the nekomata liked it when _he_ couldn’t figure out how his body worked.

But thankfully, after nearly forty minutes of struggling, Tadashi finally figured out what Mochi was trying to say.

“So I just focus on finding Hiro, like his soul or something, within the body and I...push off of it? And then I should just...separate?”

“Like oil and water,” the nekomata confirmed.

“Okay, it’s worth a shot.” Tadashi looked down at his hands, _Hiro’s_ hands. Though they were smaller and thinner they were almost as familiar to him as his own, the multiple calluses and scars practically mirrored on his own hands. Hiro’s arms, scrawny and smooth, his skin far too pale after weeks of cooping himself up indoors. Hiro’s baggy clothing that practically swamped his frame, comfortable but ill-fitting. His hands sunk once more into Hiro’s thick hair, tugging at the strands. He’d never let his hair grow this long, and the foreign feeling of it tickling the back of his neck was enough to help him focus on the fact that this was _Hiro_ , it was _Hiro’s_ body, not his own. This was his baby brother.

And just like that he could see the disconnect.

After that, it was as simple as breathing to just reach out and _pull_ himself out. It kind of felt like taking off a particularly tight set of wet pants, like fabric clinging and catching and not wanting to let go, except it was all over his body and the fabric was Hiro. But with a ‘pop’ Tadashi came loose, Hiro’s body falling to the ground. Baymax had to quickly drop Mochi in order to catch Hiro before he could hit the ground, to the cat’s unpleasant surprise. Tadashi didn’t feel too sorry for him at the moment. Mochi darted out of the garage, looking back at them all with a miffed expression and a toss of his tails.

Baymax quickly scanned Hiro to check him for any injuries, and announced that other than a slight electrolyte imbalance Hiro was completely fine, but Tadashi almost didn’t hear him. He suddenly felt impossibly tired, like all of his energy had been sucked out to remain with Hiro. Even his hitodama looked exhausted, drooping low enough that they practically skimmed the ground every other orbit.

He stuck around just long enough to watch Baymax help a groggy but awake Hiro to his feet before he decided he needed to lay down for a while. Even though the couch was nothing but ashes at this point, the thought of dragging himself up three flights of stairs, even if he could just walk through the walls, almost made him want to cry. So he flopped down on the ruins of the couch, shifting in the pile of ashes and soot just enough to get comfortable, and then let his eyes slide shut. He had just enough time to marvel at the idea that ghosts actually _could_ sleep before he faded.

Baymax didn’t see him go, because he was too busy taking care of Hiro. The robot carefully set Hiro on his feet and then took a step back, though staying close enough that he would be able to catch Hiro if he passed out again.

“Ugh, what happened?” Hiro asked confusedly, rubbing at his head. “Baymax?”

Baymax looked down at him. “You have experienced a phenomena known as possess - ”

The robot didn’t get to complete his diagnosis, because at that moment Hiro spotted the remains of the couch. “Aww man!” he shouted, pushing past the robot and running over. He looked at the pile of ashes with a mixture of annoyance, confusion, and dismay. “What the heck happened? Was this from the computer? And, dude! Where did your armour go? Oh god, what time is it?”

Rather than wait for an explanation, Hiro immediately started dashing around the garage, gathering up the discarded pieces of Baymax’s armour and slotting them back into place. “Nevermind, buddy, we’ll fix that later. Now come on, we’ve lost so much time! We’ve got to go after that guy with the mask!”

Unable to stop the whirlwind that was Hiro Hamada with a mission, Baymax dutifully followed after him into the night. Left behind, invisible and asleep, Tadashi slept right through their departure, blissfully unaware of the dangers they would soon face.


	5. Flight

It was probably a very good thing Tadashi had fallen ‘asleep’ because if he had watched his younger brother and his best friends drive a car off of a dock into the San Fransokyo Bay to escape the Onryo’s shadows, he probably would have died _again_ of a heart attack. As it was, he didn’t wake up for quite some time, exhausted from the first true use of his powers. He slept through Hiro and Baymax returning with the others and through their various experiments and tests, working together to create their ‘upgrades’. By the time he woke up, the team had finished creating their suits, and had gone off again to Fred’s place to test them, so when Tadashi opened his eyes, he was alone.

He jolted upright, immediately frantic considering the last time he’d seen Hiro the brat had been dead-set on confronting the masked man. A quick glance at the garage showed that Hiro was definitely not there, so he quickly rushed up the stairs, praying that Hiro had just gone to bed or school or _something_ , as long as he hadn’t gone after the Onryo.

He was halfway up the stairs and through the cafe when he suddenly heard his Aunt’s voice. From the sounds of it she was on the phone with someone, and she sounded quite pleased. Curious, despite himself, Tadashi made a quick detour into the cafe’s kitchen, where their phone hung on the wall.

“No, that’s great, honey!” Aunt Cass said cheerfully, holding the phone between her ear and shoulder so her hands were free to roll out dough for her well-known and beloved Cat’s Paw Pastries. “I’m happy to hear you’re getting out there and having fun. Of course you can sleep over at Fred’s place! Did you pack enough clothes? Do you have your toothbrush? When will you be coming home?”

She paused for a moment to listen to the person on the other side. It must have been Hiro, Tadashi had no idea who else she would talk to like that. So Hiro was over at Fred’s. Good, that was a relief. He then snickered to himself as he tried to picture Hiro’s reaction upon seeing Fred’s home. 

He had to admit, he himself had been more than a little shocked the one time Fred had invited him over. They were the only members of the ‘Nerd Lab’ who’d had any interest in baseball, so when Honey Lemon had won a pair of tickets as a prize at one of her baking competitions, she’d happily passed them on to the two of them. They’d gone out, had a great time, and unfortunately had a few drinks too many. Tadashi hadn’t felt safe driving his scooter home, and was prepared to take the bus, when Fred had offered a room at his place which was supposedly nearby. Tadashi had gratefully accepted, and been completely shocked when a limo had shown up to take them there. He’d been even more shocked to see the actual house. Fred had quietly admitted that he was reluctant to tell the others about his family and their wealth, in case they treated him differently, but Tadashi had simply laughed and stolen the hat off of Fred’s head before running off into the large mansion to explore. Sure enough, once they returned to the nerd lab nothing had changed between them. Hiro would be in good hands with Fred, Tadashi thought fondly to himself.

Although, on further consideration, he was still going to go check on them. It wasn’t as if he, as a ghost, had anything better to do, unless he wanted to sit around here and watch Aunt Cass bake. But if he remembered correctly from that one time he’d been there, Fred’s place was all the way on the other side of town, and Tadashi was pretty sure a ghost couldn’t drive a scooter. He sighed dispairingly. Maybe he could sneak onto a city bus or something.

He snuck out of the kitchen, leaving Aunt Cass behind as she continued to pepper Hiro with well-meaning but embarrassing questions.

As he stepped out of the cafe through the door, he had to pause for a moment to blink in the late afternoon sunlight. He glanced around, trying to remember from the days before his scooter where the nearest bus station was. One of the great things about San Fransokyo was that it had an excellent transit system. So long as he made it to the main hub near the center of the city, he could pretty much get anywhere.

He wandered his way to the bus stop, ready to wait there for as long as it took for a bus to come so he could sneak on, but when he arrived at the stop he was surprised to see the area already full of people. However there were really only two normal humans there, a young couple that seemed oblivious to everything but each other. The rest of the crowd were all supernatural creatures and spirits.

For the most part they ignored him, which gave him a chance to look them over. There was a pair of ghosts like himself, only they lacked the hitodama and instead were wearing clothes about twenty years out of date. They were watching the couple with a fond expression, and Tadashi couldn’t help but notice that the boy looked a lot like them. They must have been his parents or grandparents. Behind them was what looked like a walking tree person, who was carefully plucking a few dead leaves from what Tadashi assumed was it’s elbow. As he watched, a pure white bird hopped out of a nest it had made on the tree-person’s head and landed on its shoulder with a happy chirp. A pair of tanuki sat on top of the bus shelter and laughed as they threw stones at the head of an Oni standing on the curb, wearing a pair of glasses and trying to read a newspaper. Every time he got hit with a rock, he’d roar and look up from his paper, and the tanuki would quickly hide behind the roof where he couldn’t see them, until he returned to his paper. Then they’d do it all again. A set of three women were standing together inside the bus shelter and gossiping, though Tadashi couldn’t seem to tell if they were very old or very young or something in between. Every time he looked at them they seemed to change. Unnerved, he looked away.

The final person standing with him was quite different than anything he’d seen yet. It was short, almost as short as Hiro, blinking up at him with curious yellow eyes. When it noticed him looking back, it jumped a little, and had the decency to blush.

“Hello,” Tadashi greeted the creature carefully. It hadn’t been hostile yet, and no one else seemed to be particularly concerned by the creature’s presence, but Tadashi had heard enough stories about Kappa to recognize one and be wary. The turtle-like creature ducked its head, though it was careful to keep the shallow well of water on its skull steady so that nothing spilled out. Its hands grabbed at the ends of the rough-spun tunic it was wearing, twisting the hem nervously.

“Hi,” the Kappa returned shyly, still watching him. Its voice was soft, and kind of squeaky, so Tadashi guessed it was a young girl. She blinked at him, still blushing. “You’re new,” she told him simply.

“Uh, yeah,” Tadashi agreed, rubbing the back of his neck nervously. “How could you tell?”

She smiled bashfully at him. “Because I’ve never seen you here before. And I always catch the Thrice-Ten express.”

Tadashi’s eyebrows furrowed in confusion. Unless they’d changed the numbering system of the city buses since he was last taking transit, she was talking about something different. “Uh, come again?” he asked.

She giggled cutely and pointed upward. “There.”

Tadashi followed her finger and immediately his eyes widened in shock. Swooping down towards them out of the sky was an absolutely _massive_ persian-style area rug, its golden tassels flapping jauntily in the wind as it came in for a landing. The whole thing floated down slowly and gracefully, swinging in a wide arc around the surrounding rooftops to avoid getting caught on them, before fluttering to a landing directly next to the bus stop. Once it had stopped the carpet came to a standstill, fluttering a few feet off the ground next to the sidewalk. The whole thing was easily the width of the street, which should have been blocking traffic, but for some reason the normally busy road was mysteriously empty at the moment. The human couple, who were still occupied with each other, didn’t seem to notice a thing.

A man that Tadashi could only describe as a djinn was seated in the middle of the carpet, watching them all with a bored expression.

The supernatural folk, minus the ghost couple who lingered with the humans, all started filing onto the carpet, taking their seats gingerly across its patterned surface with the air of having done it many times before. Actually, if it weren’t for the fact that it was a magical flying carpet and none of the riders were human, Tadashi would not have been able to distinguish the scene from any typical morning commute. As he watched, the Oni took his seat and pulled his newspaper back out, grumbling to himself about stocks.

The little Kappa girl was the last to board, and she stopped when she realized he wasn’t following. She looked back at him and held out a webbed hand, blushing again but smiling reassuringly.

“Come on, I’ll show you how it works,” she offered.

And how could Tadashi pass up the opportunity to ride a _magic carpet_? With a bright grin, he took the Kappa girl’s hand, and gingerly stepped onto the carpet. He was pleased when it easily held his weight, with only the slightest warping of the fabric. The Kappa girl quickly headed to the front of the rug, and gestured him to sit down. Once they were both seated, the djinn huffed and raised his arms, causing the carpet to leap into the air. And then they were off.

It was incredible. Tadashi was very glad that the Kappa girl had brought him to the front because it gave him the chance to see the whole city spread out far below him as they flew on by, shimmering in the setting sun like piles of gold. Soon they entered the downtown core, the tall skyscrapers rising into the air around them, their smooth glass surfaces reflecting the carpet as it passed. He gasped as they shot upward, over the tallest skyscraper in the city, high enough that Tadashi could reach up and touch the low-hanging clouds, and then just as suddenly went into a sharp dive. He felt his stomach jolt as they dove, sweeping low under one of the many giant Torii gates that dotted the city’s landscape, coming close enough to the bright red wood that the tall Oni had to duck his head without once looking up from his paper. Then the carpet skimmed along the main road, hovering just above the roofs of the passing cars. On the street below, he spotted a familiar faun and his glowing children, all of whom waved up at them as they passed. The little Kappa girl and Tadashi waved back, practically giddy, as the carpet picked up speed to zoom away, leaving the glowing children far behind.

Tadashi’s hair was more than a little windswept by the time they reached their first stop, and his face would have been flushed bright red if he was still alive. He was practically shaking with excitement, thrilled at this new experience. He _loved_ flying.

“Oh man, I am never taking the bus again,” he told the Kappa girl.

Most of the passengers departed at the first stop, and a few more boarded. Soon they were off once more, and Tadashi couldn’t resist letting out a hoot of excitement. Thankfully no one seemed to notice, other than the Kappa girl who simply giggled at him. As they flew over the city again, swinging out over the bay, she started pointing out different landmarks to him. Some he recognized from the city he’d known when he was alive, a few more were new to him, parts of the supernatural world he’d woken to. He asked her as many questions as he could think of, to the point she was struggling to find answers. However, the other passengers must have been listening in, because soon they were chatting with him too, explaining what they knew and telling him stories about the city. Tadashi listened with rapt attention, so focused he hardly noticed when they set down again.

They were at the bank of the Stowmida river that flowed through the middle of the city, near the center of one of the city’s many riverside parks. He could see a group of Kappa playing in the water, and he glanced down at the Kappa girl.

“This is my stop,” she told him regretfully. “I take the Thrice-Ten express every morning uptown to visit my childhood friend who likes to grow cucumbers for me and my family, and then I come back here in the afternoon. Your stop will be next.”

“Thank you for all your help,” Tadashi told her gratefully, bowing his head respectively. She bobbed hers in return. “I’ll have to come by some time to visit!”

She immediately brightened. “Oh, yes. That would be wonderful.”

Then she hopped off of the carpet and raced across the grass to throw herself into the arms of an elderly looking Kappa who caught her with a great belly laugh. Tadashi watched the Kappa family playing happily in the river from the carpet until they became specks below, and then he could no longer see them.

Sure enough, just as the Kappa girl said, the flying carpet stopped just outside of Fred’s sprawling manor next, though Tadashi never told the djinn where he wanted to go. He glanced back at the blue-skinned man, wondering if he had to pay a fare or something, but the djinn merely waved him on, no change to his bored expression. Not wanting to question his luck, Tadashi quickly stepped off of the carpet, landing hard on the sidewalk beyond. By the time he turned around to wave, the carpet was already shooting off into the sky like a comet, the golden tassels like its fiery tail. He waved anyways, too happy to care.

That excitedly happy mood faded pretty quickly when it took him nearly an hour to finally find his brother and his friends. He’d only been to the manor once after all, and even though he could walk through walls, there were still a lot of rooms to search. But when he did find them, his heart melted when he saw them all curled up together in a pile of pillows and blankets on the floor of Fred’s rather unique bedroom, with Baymax acting as a pillow in the middle. The robot looked up and blinked at him when he phased into the room, but Tadashi quickly raised his finger to his lips so that Baymax wouldn’t wake anyone. Thankfully the robot understood, and returned to watching his patients.

The image was honestly so adorable that Tadashi wished Aunt Cass was here with her camera. Baymax was lying flat on his back, with Hiro sprawled face down on top of his large belly, snoring lightly with his cheek mashed up against the soft vinyl. Honey Lemon and GoGo were curled up together, tucked under Baymax’s right arm, while Wasabi was lying propped up against Baymax’s left side with his arms and legs crossed. Fred had flopped down across Baymax’s stubby legs, his knees and shoulders supported by one each, but his neck and head hanging down at an awkward looking angle. Baymax had his heater going at low power, keeping everyone warm and cozy.

With a fond smile, Tadashi started moving around the room. He wasn’t sure if he could actually do this, but to his pleasant surprise he found that if he concentrated intently, he could manage to grudgingly interact with physical objects. With a grunt of effort he dug his fingers into the soft plush of a throw pillow, and started dragging it across to where Fred was lying. It took way too long, and an embarrassing amount of strength to get the pillow under Fred’s head enough that his friend was no longer going to wake up with extreme neck pain. Once that was in place, Tadashi started grabbing blankets, throwing them across everyone to keep them warm. He was happy to discover that the more he tried to move, the easier it became, until draping the blanket across Hiro felt as normal as every time he’d done it back when he’d been alive. Unable to resist, he leaned down and pressed a soft kiss to Hiro’s forehead, even though he couldn’t actually come in contact with his brother. It still made him feel better.

His task complete, Tadashi settled down for the night, finding a spot next to a pile of what he assumed was Fred’s cosplay gear, though none of the outfits were any characters he recognized, and he was pretty sure at least two were meant for women if the bright orange purse with a heart-shaped keypad on the side was any indication. Then again, Fred was a funny one.

Tadashi had slept long enough earlier that he didn’t need to now, even after all of his exertions getting everyone tucked in, so he simply closed his eyes and basked in the feeling of being surrounded by his friends again.

+++

Tadashi was torn between laughing out loud, crying, and ripping his own hair out. His friends had gone and made themselves _super suits_ to confront the masked Onryo they were now calling ‘Yokai’ (courtesy of Fred), thinking he was some sort of super villain bent on causing destruction or something. They had no idea that the man they were going to confront wasn’t a man at all, and that he would be completely immune to everything they were developing.

Which was too bad, because honestly the suits were things of beauty. Tadashi couldn’t help but be impressed. With Hiro’s help, the team had managed to turn their projects, some which actually took up the space of _rooms_ like in the case of Wasabi’s lasers and Honey’s chem lab, and compress them into weapons they could actually wield. Tadashi had always known that Hiro was brilliant, but this was the first time he’d _really_ seen Hiro use his gift. It was humbling, and more than a little terrifying considering the intent behind it, but Tadashi still felt his chest practically bursting with pride. It was strong enough that he actually had to step away for a bit in case his hitodama took it as an excuse to start causing trouble.

He also kept his distance after the first time he realized that his presence might mess with the complicated circuitry in everyone’s suits. GoGo had been the first victim. He’d been insanely curious about how Hiro had managed to miniaturize and attach her electromag suspension to her feet, and had leaned in for a closer look, when all of the sudden the electromag gave out. GoGo was unceremoniously dropped to the ground while her two wheels rolled away in either direction like loose hubcaps. Tadashi remembered enough about the computer in the garage and Baymax’s comment about the electrical anomalies in his circuits to realize he’d caused a problem again, and quickly stepped away. Almost immediately GoGo’s suit seemed to return to normal, thankfully, which at least meant his effects weren’t permanent. The rest of the day he paced on the edges of the garden, watching each of his friends try out their new equipment, and trying to figure out how close he could get before he started causing things to go on the fritz.

What sent him over the edge though was Hiro’s ‘upgrades’ to Baymax. Tadashi had pretty much accepted at this point that Hiro was going to turn Baymax into a fighting robot regardless of his original purpose, and the cherry red armour _was_ very impressive, but _wings? Flight?!_ Then the pair actually took off.

Or rather fell over and then crashed through the garden like a rogue rocket. And into Tadashi, who was apparently a bit too solid at the moment.

“Uh oh,” Wasabi said, as the rest of the group was left behind in the garden, watching with wide eyes as Hiro and Baymax become a speck in the distance.

Tadashi was sort of really glad for once that Hiro couldn’t actually hear him, because his high pitched screaming was more than a little embarrassing. He was smooshed against Baymax’s helmeted face, probably messing with the circuitry and wires inside, going what felt like mach one above a busy city street, doing his best to make himself as solid as possible against Baymax’s metal armour, because if he suddenly phased through right now he was going to find out if ghosts could become street pizza. It didn’t help that Baymax seemed to be struggling to stabilize, and Hiro’s directions were only becoming more frantic as they headed deeper into the city.

Suddenly Hiro let out a scream, and Tadashi distractedly struggled to look over his shoulder, only to see they were headed straight for a giant mechanical cat statute on the roof of a sushi shop.

“Thrust, thrust, thrust!” Hiro ordered frantically.

Baymax obeyed just in time, swinging his rocket boots downwards and launching the three of them straight up into the air. It was enough to jolt Tadashi off of his precarious perch, and the ghost let out another scream as he was suddenly tumbling. He threw out a hand and focused all of his attention on grabbing on to something solid, and nearly cried in relief when he managed to grab hold of one of Baymax’s wings. He was trying to find a second handhold when Baymax responded to Hiro’s frenzied commands by cutting off his rockets completely.

They reached the top of their arc, Tadashi hanging on with one hand and almost floating alongside them for a moment, and then Baymax started to fall.

“No. No, no, no!” Hiro and Tadashi practically stuttered as one.

The pair screamed again as Baymax fired his rocket boots just in time, shooting across the rush hour traffic on the Golden Torii Gate Bridge and narrowly avoiding splattering them into the back of a truck. By the time Baymax managed to bring them in for a (surprisingly) gentle landing on the top of the south tower, Tadashi was pretty sure both of them were going to need a shock from Baymax’s defibrillator palms.

“Oh man, maybe that’s enough flying for today,” Hiro suggested, his voice breathless. Tadashi, who had only just readjusted himself so he was clinging to Baymax’s back with more than just one hand, couldn’t agree more.

And then Baymax got it into his head that flying was actually somehow improving Hiro’s health.

“Oh no,” Tadashi moaned as the three of them slowly tipped over the edge.

But very quickly the brothers’ terrified cries turned to cheers of excitement as Baymax finally got the hang of using his flight programing. Soon they were shooting through the city, faster than even the magic carpet, and pulling so many aerial stunts that Tadashi lost track of which way was up. He and Hiro were laughing like loons, grinning with the wind in their faces, and for a brief moment, when Hiro turned to look at his reflection in a passing window and ended up looking almost directly at Tadashi, it almost felt like the fire had never happened. It was just the two of them testing out another crazy invention and almost getting themselves killed, but they were together, just like it used to be.

But then Hiro’s arms went up over his head as he whooped, and his fist passed straight through Tadashi’s chest, and the moment was broken. His happy grin faltered for a moment, but he quickly pushed his sadness aside. Right now he was having a blast, Hiro was also having a blast, and he wasn’t going to let anything affect that.

By the time they settled on one of the large wind turbines above the city, Tadashi was left breathless. Even his view from the magic carpet couldn’t compare to what he saw now. The city looked like a model from this high up, so far up that the cars were like ants moving below them. A sinuous oriental dragon swooped by over their heads in a flash of silver scales, on its way to tending the wind turbines. Tadashi chuckled at the sight. He’d always thought it must have taken at least a little bit of magic to get those things up in the air.

The three of them sat in happy silence for a while, watching the sun slowly set on their home. It was nice to just sit still and bask for a while, especially after the recent chaos that was their lives. Tadashi caught Baymax glance over in his general direction at least once, which meant the robot knew he was there even if he couldn’t be seen, but thankfully he didn’t bring it up. Tadashi was pretty sure any mention of him at this point would spoil the mood, and that was the last thing he wanted.

All too soon though, Hiro was ordering Baymax to fire up his improved scanner. Tadashi wasn’t sure exactly what Baymax was scanning for, maybe electrical disturbances from ghosts, or for the microbots themselves, but he found it soon on one of the islands out in the San Fransokyo Bay. To Tadashi, the island looked like a lurking beast looming out over the waters, waiting for them to come close enough to pounce on them and swallow them whole. That was where the Onryo awaited them.

He shuddered, tucking himself closer to Hiro’s side and tried his best to pretend he could protect Hiro from the creature they’d soon be facing.

**Notes for the Chapter:**

> Sorry for the delay on this one, life got kind of intense for us for a little bit, and then Ikira was away for the weekend. Hopefully the wait wasn't too much trouble!


	6. Conflict

**Notes for the Chapter:**

> Sorry for the delay everyone! Ikira's laptop died pretty much an hour after posting the last chapter, and we weren't able to edit the next chapter until she got a new one. But we're back in business, with an extra long chapter to make up for it. Enjoy >:)

Tadashi had taken one look at how the team was going to be carried to the island and immediately known he wouldn’t be able to ride with them. There wasn’t enough space for him to cling to Baymax’s armour without sitting far too close to everyone’s suits, and he _really_ did not want to find out what would happen to them if they started fritzing out in midair over the waters of the Bay. But there was also no way he was letting them all go without him. So the moment the group took off, he raced across Fred’s property, heading for the street and the nearest bus stop. The magic carpet was the only way he could think of to get to the island with the others, unless he wanted to swim the whole way.

But to his shock, when he reached the street someone was already standing outside and waiting for him.

Mrs Matsuda cackled at his slack-jawed stare as she stood there leaning against an absolutely massive mortar and pestle that looked to be carved from solid granite, and covered in strange runes. A few of her more fanciful stories from her youth suddenly came to mind, and he recalled how in some of them, where she called herself Baba Yaga, she’d somehow travelled in a magical mortar and pestle. He’d thought she’d just been telling stories, but he couldn’t deny what his eyes were seeing now.

“Hello there, boy!” She chortled, her grin wide enough to show of rows and rows of pointy iron coloured teeth. “Heard you might need a lift!”

“O-obaa-san!” Tadashi stuttered, stumbling towards her despite his shock. “Yeah, I do, but...how did you know?”

“Ha! I have my ways, or have you forgotten the crystal ball I had you clean practically every morning?” She shook a long bony finger at him admonishingly. “I also gave you a little trinket when you first left my home. Clever little thing activates when you need me.”

Tadashi’s mind drew a blank for a moment, but then his expression cleared. He dug his fist into his pocket and pulled out the old antique amulet she’d shoved into his hands all those days ago as he’d left her house. At the time he’d thought nothing of the necklace, piled on top of all the other things she’d handed him, but now he saw the center stone was glowing the same colour as her crystal ball.

“That’s the one,” she confirmed at the sight of it. “Now hurry up. I haven’t got all day, and I left a goblin stew on the fireplace back home. Get in, chop chop!”

Tadashi eyed the giant mortar which, while large enough to fit a person, might be a bit squishy for the two of them. He hesitated, taking a tentative step backward. But then Mrs Matsuda, impatient, reached out and pinched his arm, making him yelp. When she lifted the pestle in a threatening manner, Tadashi got the hint. He was quick to scurry into the mortar, despite his misgivings. Even if it was squishy, it would be better than getting pinched again, or smacked with the pestle.

But to his surprise, once he was seated inside, it was much roomier than he’d thought. It was almost as if the mortar had grown in size to accommodate the extra passenger, but he hadn’t seen it change at all.

“Unbelievable,” he murmured to himself.

But before he could comment further, Mrs Matsuda was shoving herself into the mortar next to him and settling herself down, her pointy, bony knees digging into his sides as she got comfortable. Then, with another cackle and a shove from her pestle, they were suddenly airborne.

As the world passed by beneath them in a blur, Tadashi pointedly did _not_ think about how a stone bowl the size of a washing machine could somehow _fly_. He was starting to get used to the whole supernatural thing, but there were still some things too weird for him to think about.

Unlike flying with Baymax or the Carpet, flying with Mrs Matsuda was not nearly as fun. She flew straight and true, with no embellishments or loops, heading undeterrably for the island where the Onryo was supposedly waiting. That was fine, though, because Tadashi wasn’t really in the mood for sight-seeing right now. He was too busy worrying about his brother and friends, and if they’d found the Onryo by now.

Thankfully, Mrs Matsuda’s direct route got them to the island quickly enough. When they arrived on the island, they could already faintly hear the sounds of battle coming from inside, causing Tadashi’s breath to hitch. He scrambled out of the pestle, glancing around the island for any sign of Hiro and the others.

“This is where I leave you, boy,” Mrs Matsuda said gravely from behind him, leaning heavily on her pestle like a walking stick. “From here on out, you’re on your own.”

Tadashi looked back at the old woman, a protest already forming on his lips, but one look at her serious expression told him he would not be able to convince her otherwise. He knew from her stories that it was her nature to help only a bit at best, and that she expected him to be able to solve his problems on his own. She wouldn’t hold his hand and lead him. So instead he simply bowed respectively. “Thank you for all of your help, Obaa-san.”

She nodded back to him, and then with a shove of her pestle, she was off again, flying through the sky and back towards the city. Tadashi didn’t watch her go, though. He was already heading into the abandoned facility.

He was never more grateful for his ability to walk through walls than he was at that moment, because it made it ridiculously easy to just head straight for the sounds of struggle and ignore any obstacles in his way. That was a very good thing, because when he arrived it was just in time to see the team losing. Badly.

It was bad enough that they apparently didn’t have a plan and couldn’t work as a team yet, but what was worse was that nothing they threw at the Onryo could touch him. If their blows weren’t blocked by the ever-present shadows, they passed right through his incorporeal body. Their gear would also start sparking slightly if they got too close. They clearly thought it was their equipment failing, unaware of the Onryo’s supernatural influence over their electronics. Honey Lemon at least had noticed this by this point, because she was hanging back and desperately creating as many different chem balls as she could think of, trying each one to see what would work. The others were too busy trying to keep from being torn apart by the shadows to have noticed what was happening.

But then, to Tadashi’s horror, Hiro tried to swoop in on Baymax to steal the mask off of the Onryo’s face, only to be knocked loose by a violent swipe of a shadow tendril. Baymax went flying, while Hiro crashed to the ground, skidding along until he was stopped by a large metal pipe just below the catwalk Tadashi was standing on. Thankfully Hiro’s suit and helmet took the brunt of the impact, but he was still left dazed for a moment. The Onryo suddenly whirled on him, golden eyes and lone hitodama flashing, sensing easy prey.

“No!” Tadashi screamed. Before he could stop to think about it, he was already jumping. He just knew he needed to get between Hiro and this monster as fast as he could, whatever the consequences. His eyes narrowed and his hitodama flared up as he whistled through the air, aiming to land on the ground right in front of Hiro so he could protect him.

But then Hiro groaned and rolled over a bit, and instead of landing in front of him as Tadashi had planned, Tadashi landed _in_ him. Rolling with it, Tadashi fought off the now-familiar disorientation of possessing Hiro and managed to look up just as the Onryo’s fist came down. The memory of ice cold shadows snaking down his throat danced through Tadashi’s head.

Even though Hiro was human, even though Tadashi was weaker than the Onryo, even though he was still dizzy from the shift into Hiro’s body, Tadashi was still a black belt in karate, and some habits were hard to break. His karate training kicked in before he could stop himself, and he brought up his arm to block even though he knew it was hopeless. His eyes squeezed shut and he braced himself for the familiar choking cold feeling from before.

Except there was no cold. Just the solid collision of flesh meeting a gloved hand. The whole room seemed to pause for a moment as it registered that for the first time someone had actually managed to come in contact with Yokai. Tadashi himself was stuck trying to figure out how he’d just done that. Even the Onryo somehow looked shocked past his mask.

“Uh…” Tadashi hesitated for a second, lost. Then, it suddenly hit him. He could actually fight the Onryo! It was just like he suspected, possessing Hiro had given him the boost in power necessary to fight back. He was strong enough now!

With a smirk, Tadashi pulled back Hiro’s scrawny arm, keeping the line of it firm like he had been taught, and with all the strength he had in Hiro’s smaller body he struck, burying Hiro’s fist into the Onryo’s stomach. 

Though there was no way Hiro was strong enough, the punch sent Yokai soaring across the room like he’d been shot out of a canon, leaving his shadows scrambling after him. Tadashi stood there a moment, blinking in shock, before quickly scrambling to his feet. There was no way he could miss out on this opportunity now. With the sounds of his friends gasping in shock and Fred cheering him on in the background, Tadashi raced across the room towards where Yokai was just being helped to his feet by the shadows. The Onryo only had enough time to look up before Tadashi’s leg was kicking out at him from the side, sweeping his feet out from under him. Yokai went down hard, grunting in pain and anger.

But before Tadashi could hit him again, the shadows lashed out, driving him back. Tadashi was forced to jump away to avoid getting hit, dodging and skipping backwards as they struck like snakes at his exposed shins. A particularly fast one managed to land a hit, cutting into his arm.

Tadashi hissed in surprise, but compared to back in the warehouse, he barely felt the strike. It was like Hiro’s body protected him, though he was reluctant to test out the theory. There was no way he was using Hiro as a human shield. It was bad enough he was possessing his little brother.

Tadashi narrowed his eyes at the shadows consideringly as he rubbed at his injured arm. They were going to be a huge obstacle if he wanted to get to the Onryo, constantly attacking him and distracting him, and they might hurt Hiro. He needed to get rid of them, and fast, he thought, a plan already coming to mind.

What better way to get rid of a few shadows, than with light?

He’d never really consciously used his hitodama, not like this. He’d always been a bit afraid of them, even when he’d realized they weren’t going to hurt him, because of the danger they could become. But when he reached out to them, they responded like they were part of him, like limbs he’d never known existed. They started whirling around him at his command, faster and faster, and growing brighter and bigger, until they were like a flaming halo around Hiro’s head, mimicking the golden light of his eyes. With a gesture, Tadashi sent the ring of fire swinging closer to the shadows, which to his satisfaction flinched backwards. Increasing the flame’s power sent the shadows scrambling, until it was just the Onryo before him, looking around himself in a panic at his sudden abandonment.

The painted mask finally turned towards Tadashi as the dark spirit tried to prepare himself for the fight. Tadashi nearly laughed out loud at the sight. The Onryo’s stance was all wrong, his feet too close together, his arms too far apart. The man had probably never been in an actual fight in his life. This was going to be far too easy.

And sure enough, it was. Even in Hiro’s tinier body, which was almost too short to properly reach the Onryo’s face with a punch, it was completely one-sided. Every time the Onryo lashed out with a punch or kick, Tadashi seemed to see it coming a mile away.

At first he’d fallen back on his own habits of blocking the hits, because he was used to having a larger and bulkier body, but all too soon he realized he could take advantage of Hiro’s smaller frame and avoid the chance of his brother getting hurt. Soon he was ducking and weaving under each blow, practically laughing in the Onryo’s face as he lept over another poor attempt at a sweep kick and then crouched under a weak punch. He could hear the Onryo panting underneath his mask, and each attack was growing more uncoordinated. Tadashi himself had riddled the Onryo’s body with a few hits of his own, taking advantage of the other spirit’s poor defence to land a kick that would have bruised his kidneys if he were still alive. The entire time the two were fighting, Tadashi’s hitodama circled, keeping the hissing shadows at bay.

Finally Tadashi decided enough was enough. The Onryo didn’t seem to want to accept defeat, so it was time for Tadashi to end things once and for all. He waited until the next time Yokai tried a forward punch, ducking and then moving inside the spirit’s guard. Then, when Yokai was still off balance, Tadashi brought up his fist in the strongest uppercut he could manage. Yokai’s head snapped back and he went flying, his kabuki mask soaring in the opposite direction to clatter to the ground at Wasabi’s feet. The dark-skinned man, who was in the middle of trying to help Baymax out from under the rubble he’d been buried in, looked up when it landed.

Wasabi tentatively picked up the mask, studying it in confusion. “Uh, guys? There’s no neurotransmitter here. How the heck is he controlling that black stuff without a neurotransmitter?”

No one answered him though, because they were too busy staring. Yokai had painfully pulled himself to his feet, and finally turned to face the assembled onlookers. To the humans in the room his face looked vaguely familiar, but warped beyond recognition. The skin was white as paper shot through with green and purple veins, the mouth full of blackened teeth that protruded past thin lips like tusks. The eyes were hollow and sunken, and glowed dimly like embers.

But to Tadashi, the face was something much different, someone much more familiar. He felt his heart go cold.

“Professor Callaghan?” he whispered brokenly. His whole body felt like it had been dunked in ice water. Without his attention, his hitodama suddenly guttered and shrank, floating back to his side like loyal dogs slinking back to their master. Tadashi didn’t notice them though. His entire world had narrowed down to the spirit before him, his once wise friendly face twisted up into an expression of hatred and cruelty.

It was Professor Callaghan. Tadashi couldn’t deny it, as much as he wanted to. As much as his mind and soul were _screaming_ for him to. It was the professor. But it was not the Professor he’d once known.

“Oh my god. It was _you_ who started the fire? You...you started it. You caused it.” Tadashi felt his mind go blank, even as he started slowly backing away from the man he had once almost considered a father figure, shaking his head in disbelief. “It was _you_?”

There was a strange ringing in Tadashi’s ears, making it hard to hear anything. And underneath it all, Tadashi could almost hear the sound of crackling flames. Almost smell smoke. But how could he smell smoke when it felt like the whole world was underwater?

“You wouldn’t understand, boy,” Callaghan hissed at him, wincing as he held the side Tadashi had kicked. Behind him, the shadows were regrouping now that Tadashi’s hitodama had shrunk, moving in dark rippling waves towards the two spirits. “Now get out of my way. I have things to do that do not concern you.”

“But you...you attacked me, in the warehouse. And you - ” Suddenly Tadashi had a flash of memory from just before his death. He could always faintly remember that there had been someone there in the flames, a shadowed figure standing over him and watching him, but he’d never quite remembered who they were or what they’d looked like. But now the memory came back to him with such clarity he couldn’t believe he’d ever forgotten.

Through smoke and flame, Callaghan had looked down at him as he’d lain there, helpless. Looked him dead in the eye. And turned away.

“It was _you_ in the fire,” Tadashi whispered. “You were there. You left me.” The almost smell of smoke became stronger, trapping itself in his lungs and making him feel like he was choking. Tadashi could feel his lungs heaving in his chest as he tried to draw in air past the anger, fear, and pain squeezing his throat shut. “You _left_ me to _die_ in the fire _you_ created!”

“You _**killed me!**_ ”

Suddenly Tadashi’s hitodama flared even brighter than before, swelling to the size of car tires, hovering over him like a set of furiously blazing suns, their power reflecting Tadashi’s rage. Callaghan cowered back in fear, sweat growing on his face from the intensity of the heat that they were throwing off, but Tadashi pressed closer. He was practically blinded with anger, overcome by the realization that all of his pain, all of his suffering, was because of this man that stood before him. A man that Tadashi had _trusted_. A man that had ultimately betrayed him, and threatened the lives of all of those Tadashi cared about. And in that moment, all Tadashi knew was that he wanted to _hurt_ something.  
But with his hitodama burning for fiercely, their light flickered menacingly over the metallic walls of the abandoned facility, the reflections for a moment made Tadashi feel like he were back in the burning showcase hall. The faint memory of his death, the feeling of being trapped beneath the rubble, helpless and burning, overcame him, making his eyes go wide and his breath catch in his throat. It was enough to break his concentration for a crucial moment, and Callaghan immediately tried to bolt.

He wasn’t going to get away that easily though. Tadashi would not allow it.

Hiro’s eyes flashed a golden blue, and the hitodama responded. A great whip of flame shot out from the closest hitodama like a sun flare, powered by Tadashi’s rage. The blaze caught Callaghan on the shoulder, knocking him off balance and making him howl in pain. His hand went up to cover the mark, but thick ichorous blood still leaked down his injured arm. He looked up at Tadashi in pure shock, unbelieving that Tadashi Hamada would ever act so violently. But one look at the dark expression on Tadashi’s face told Callaghan that Tadashi was not playing around.

With a yelp, the Onryo managed to dodge the next blast, and the one after, but he found himself cornered seconds after. He looked up in terror into Hiro’s golden eyes, the boy’s face twisted with Tadashi’s anger and betrayal. All three hitodama flared up, readying for a killing blow. Callaghan whimpered and covered his face with his hands.

But then something was between them, blocking Callaghan from Tadashi’s view. Tadashi blinked in confusion as he was suddenly confronted with a smooth expanse of red and purple armour instead of the cowering face of his murderer. He looked up to see Baymax looking down at him, his blank face unreadable.

“Tadashi, I must ask you to stop. You are becoming a danger to my patients,” Baymax told him plainly.

For the first time since the mask had been knocked off, Tadashi remembered that he wasn’t alone in the facility. He looked over at his friends, who were shrinking back against the far wall to escape the heat of his hitodama. Even through their fire-proofed suits, they looked to be sweating, and they were all looking at him nervously.

“I...oh my god,” Tadashi gasped. “Oh my god, what am I doing?” He took a step back, more a stumble than anything, his hand flying to his forehead to bury itself in Hiro’s hair. With his concentration broken, his anger faded, and his hitodama slowly shrank back to normal until they were three tiny flames again, fluttering around his head and shoulders like birds.

Callaghan didn’t wait for a second chance. The moment Tadashi’s flames were gone, he scrambled to his feet, racing towards Wasabi. The physicist yelped as the Onryo rushed at him, but rather than attacking Callaghan simply snatched the kabuki mask out of his hands and ran, phasing through the walls and pipes of the abandoned facility to disappear into the shadows that followed him.

+++

The team was left standing there, completely confused and starting to feel like they were in over their heads. They looked at Hiro, who was staring at the ground with shaking shoulders, looking like he was about to cry, then at each other. Wordlessly they all agreed that none of them had any idea what had just happened or what that confrontation had been about. What they did know was that the strange heat that had been surrounding Hiro moments before was gone, and they were finally able to move closer.

GoGo was the first to approach, although she kept her throwing disk ready in case Yokai came back or Hiro became violent again. “Hiro? Care to explain what the heck just happened?” she demanded.

But Hiro looked up at her with watery eyes and such a helpless expression that she felt her usually angry demeanor crack a little. She faltered, nearly choking on her gum. He’d seemed so confident and in control earlier but now? It was like she was looking at a completely different person.

“I...I don’t know what to tell you,” Hiro finally admitted after a moment. His voice was hoarse, and it cracked a little. After a moment he rubbed at his eyes, which were running slightly with tears.

It was enough to finally bring GoGo’s maternal instincts that she swore didn’t exist to the surface. In one smooth motion she tucked Hiro up under her chin and squeezed him tightly, ignoring the way the others gaped at her in shock. “Hey, it’s okay. Just tell us what’s going on. We’re trying to help.”

“Yeah, dude,” Fred added, reaching out with his real hand poking through the mouth of his suit to pat Hiro on the head.

“Come on, little man, you can tell us,” Wasabi came up next, smiling gently.

“Yes, Hiro!” Honey Lemon finished off the group, reaching out and adding herself to the hug. “We’re your friends. We want to be here for you.”

Hiro looked up at all of them as they surrounded him, showering him with love and support, and then smiled, though it was a little strained. “Thanks guys. You really are the best friends a guy could ask for. But…” He hesitated, and the others leaned in closer in anticipation, waiting to hear an explanation about what had just happened. “I’m not sure you’ll believe me,” Hiro finally finished.

The group let out a round of disbelieving groans.

“Man,” Wasabi moaned, “we are all wearing super suits, you weaponized your brother’s robotics project, Fred’s rich, and I’m pretty sure we just fought a ghost or something. At this point, we’ll believe _anything_ ,” he reassured. The others quickly nodded along.

“And if we don’t, Fred will,” GoGo added. Fred started to object, but a quick glance from the entire group, even Baymax, made him shrug his shoulders and grin. He couldn’t argue.

Hiro considered each of them for a moment in turn, before finally seeming to accept their words. He closed his eyes and took a deep steadying breath. “Okay. Okay,” he murmured to himself, trying to organize his thoughts. Then he opened his eyes, looked up, and spoke.

“I’m not Hiro. I’m Tadashi.”

+++

They reacted about as well as he expected. At first they’d all looked at him, like they were waiting for the punchline to a joke. When he didn’t say anything else, they started glancing at each other, trying to figure out how to respond to him. Only Fred seemed to still be watching him with the same intent expression.

When still no one spoke, Honey Lemon finally broke the silence. “Hiro, sweetie. Tadashi’s...dead. You know that right?” she asked him tentatively, leaning in close to lay a comforting hand on his shoulder.

“Yeah, I know. I know I’m dead, that’s the point. I’m a ghost,” Tadashi tried to explain. When her expression twitched, becoming more pained, he hurried his explanation. “No, I swear I’m not crazy! I’m Tadashi, I’m a ghost, and I’m possessing Hiro right now. I swear it’s true!”

The other three still looked uncertain, but Fred’s face split into a huge grin. “You’re a ghost? Dude, that’s so totally awesome! You’re like GhostMan from CD comics, using your ghostly powers to fight crime! And - ” he suddenly cut himself off with a gasp of realization. “ - and that super villain was the one that set the fire which means you’re fighting a super villain and _avenging your own death!_ Dude!”

Tadashi stared at his comic book obsessed friend and gaped. “No, that’s...well, actually, yeah. I guess that kind of _is_ what I was doing there,” he said with surprise as he thought about it. But then he quickly shook his head, trying to get back on track. “But I didn’t know he was the one who...killed me...until the mask came off! I’m not doing this for revenge, I’m trying to protect you guys. To protect Hiro.”

“Wait, are you telling me you believe him?” Wasabi asked Fred incredulously, jerking his thumb in Tadashi’s direction.

“You said he would,” Honey Lemon couldn’t help but point out.

“Nuh uh,” GoGo said with a snap of her gum. “There’s no way. That’s crazy talk.”

“Tadashi Hamada is showing no sign of mental instability,” a soothing voice broke in. The group turned to face Baymax who had raised his hand in his familiar information delivery gesture. “In fact, I am detecting that his neurotransmitter levels are all in fact normal, despite showing signs of depression and anger earlier.”

“Baymax, come on, you can’t tell me you believe him too,” Wasabi pleaded to the armoured robot.

“It… _is_ a bit hard to swallow,” Honey Lemon offered gently, always the peacemaker. “How do you know it’s him?”

“My circuitry is registering anomalies in Hiro’s presence, proportional to my distance from him. You may also be experiencing this phenomena when you approach.” The team glanced down in surprise. None of their gear had been activated when they had approached Tadashi, but now that it had been brought to their attention they were shocked to find that Baymax was right. Their gear was acting up. Wasabi further tested the theory by activating his plasma blades and then taking several steps towards and away from Tadashi, watching the blades the whole time. Sure enough whenever he got closer, the plasma would spit and fizzle, but when he moved away it was fine. “As these electrical anomalies have no other identifiable cause,” Baymax continued, “it can be concluded that Hiro is the source. As ghosts are supposedly capable of interfering with electronics and technology, it is reasonable to conclude that he may currently be possessed by one.”

“Additionally, Hiro Hamada is expressing behaviours and mannerisms identical to those of Tadashi Hamada, and is insisting that this is indeed his identity. Thus it can be concluded that the ghost in question is in fact Tadashi Hamada.”

The team stared slack jawed up at Baymax.

“Yeah, that was pretty much my reaction when he pulled this on me earlier,” Tadashi admitted to the stunned college students. “Kind of hard to argue with him though.”

Honey Lemon was the first to snap out of her shock. She took a shuddery breath and fidgeted with the hem of her suit’s dress, regaining her composure, before finally looking at him. There was a moment of hesitation, where she reached to grab the sides of his face but paused with her hands fluttering over his skin. Then, she took a determined breath and took hold, tilting up his face so that she could look deeply into his eyes. She searched them for a moment, her own eyes darting back and forth, before they suddenly widened.

“T-Tadashi?” she asked shakily. “Is it really you?”

“Yeah,” he nodded, fighting back the urge to cry in relief. “Yeah it’s me.”

She let out a choked sound that was somewhere between a sob and a laugh, and threw her arms around him. “Oh, Dios mio, Tadashi!” She buried her face in his neck and started crying, although it was a happy sound instead of sad. “We missed you so much!”

“Aww yeah, it _is_ him!” Fred crowed, jumping up and punching the air in excitement. The next moment he’d thrown himself at Tadashi and Honey, practically bouncing in excitement.

Tadashi looked over Fred’s shoulder at GoGo and Wasabi. They both still looked slightly unconvinced though, hanging back with hesitant expressions, so Tadashi tried a different tactic.

“Hey, GoGo. Remember in first year when you told me your actual full name because you needed me to take out a book for you to save you the library fees, and then swore if I ever told anyone you’d punch me so hard I’d walk funny for the rest of my life?”

Her brow furrowed for a moment as she tried to recall what he was talking about, and then her eyes went wide. “Don’t you _dare_!” she roared.

He snickered, but shook his head. “I won’t. But I will say your full initials are E.L.T.”

GoGo’s mouth dropped open, and her gum would have fallen out if she didn’t quickly snap it shut. Her face suddenly went bright red, and with a huff she crossed her arms. “Okay, I believe you. Jerk.”

Tadashi fought back the urge to laugh. Hiro’s body or not, he was pretty sure she’d punch him all the same. With a jerk of his head, he gestured her over to join in the group hug. She did with a roll of her eyes, though Tadashi couldn’t help but notice that she hugged him even harder than Fred.

Finally he glanced over at Wasabi. The dark-skinned man was looking between all of them with an expression like he was deep in thought. His brows were furrowed, his mouth had tightened into a thin line, and he was chewing on the inside of his cheek in a familiar way. He looked like he was seriously pondering about something, only Tadashi wasn’t entirely sure that it was about his identity as a ghost.

“Wasabi?” Tadashi called out hesitantly. “What is it?”

Wasabi glanced up at him, but his pensive expression didn’t change. “It’s just…I mean, I grew up in a pretty strict home, you know? My parents weren’t much for fairy tales or ghost stories or anything like that. But…I remember this little old man in church, who used to sneak me these candies before the service, and always told me I looked ‘dapper’. He passed away when I was eight, and the whole church went to the funeral, even me, but I _swear_ the next time I was in church, there he was, sitting in his usual seat at the back, offering me candy. I took it.” Wasabi’s eyes slipped closed as he fell back into the memory. “Never saw him again, but I still have the candy, it’s in my desk drawer at home. I didn’t say anything at the time because I was scared, and I’ve honestly never told anyone about it to this day. I started to think I dreamed the whole thing, except I have that little candy still sitting in my desk drawer, and I see it every time I go in there looking for a pen.”

“So I guess what I’m trying to say is...I believe you,” Wasabi finished. He let out a deep sigh, and his whole body seemed to relax, like he was letting a heavy weight slip off his shoulders.

“Thanks, Wasabi,” Tadashi said quietly, both for believing in him and for sharing his story. The others echoed him, and Wasabi smiled a bit brighter with each one.

“Okay, now that all of that is out of the way, will you _please_ tell us what’s going on?” GoGo cut in, looking more than a little frazzled. “How are you here? Why are you possessing Hiro? Is he okay? And who was the guy in the mask?”

Tadashi let out a great sigh, and leaned back until he was resting against Baymax’s broad stomach for support. He smiled a bit when his robot reached down to place a hand on his shoulder, lending him further strength. He couldn’t believe how nice it was to have Baymax there for him. The gentle robot’s presence helped him to keep calm as he gathered his thoughts in the face of his college friends. He was going to have to dredge up some unpleasant memories to explain everything and answer all of their questions, so he could use all the support he could get.

“Well, I guess I should start at the beginning, when the showcase hall caught fire…”

+++

It had been ridiculously difficult at points to talk about what had happened to him. He’d tried his best to skim over the details of his death as quickly and vaguely as possible, helped by the fact that he didn’t remember much of it himself, but his friends still looked like they were going to be sick. He’d actually needed to stop for a moment because Honey Lemon had started crying, and then _he_ had started crying, and then they were _all_ crying and hugging each other, with Baymax wrapping them all up in his massive armoured arms and holding them close. It took a few minutes to calm everyone down, and only then did he continue.

Their eyes had glittered with wonder as he told them about the strange mysterious world that existed all around them that they just couldn’t see. They’d gasped when he told them about what had happened to Hiro and himself in the warehouse, and GoGo had sworn loudly when Tadashi talked about what had happened to him when he’d gone back. Tadashi shuddered at the memory, but with his friends all around him, pressing in close, it was easy to shake it off and continue.

But then he revealed who the man in the kabuki mask was, and the group immediately started shouting loudly.

“What? No! That’s not possible!”

“But he was such a sweet man!”

“Dude, the prof went Darkside?”

“Tadashi,” GoGo looked straight at him, her expression serious. “Are you sure? We...we couldn’t really see his face, it was...warped or something, even if it _did_ look familiar. But are you sure?”

Tadashi nodded back, just as serious. “To me, it was clear as day. It was Professor Callaghan who set the fire. He died in it with me, and became a ghost too, but different. I think he’s an Onryo, a vengeful ghost that attacks the living.”

The group fell silent for a moment as they tried to absorb everything, and reconcile their memories of the warm and caring professor with the monster that had chased them into the Bay and tried to kill them. Honey Lemon looked up at him sadly.

“But...but why?” she finally asked for all of them. “We thought Yokai started the fire to steal Hiro’s microbots, but if he’s dead too then why? Why would he take them? And who does he want vengeance on?”

Unfortunately Tadashi didn’t have an answer. “I...I don’t know. I think taking the microbots was his original plan, but afterwards, when he didn’t need them...I think he picked them up by mistake. But he did want them. I saw him headed for the neurocranial transmitter when he...” 

Tadashi fell silent, the memory of Callaghan leaving him to die overwhelming him for a moment. Thankfully, his friends were smart enough to understand what he wasn’t saying. Once Tadashi was able to speak past the lump in his throat, he continued. “He needed them for something, when he was alive, probably his revenge, but now? Now he’s an Onryo, and he has those shadows instead.”

“Oh man, this is so cool! He’s got superpowers!” Fred suddenly burst out, sounding very excited. “And he plans to use them for revenge! But you’re a ghost too so you used _your_ ghostly powers to stop him! It’s like you’re SuperGuy and he’s General Doz! Oh wait, but you’re supposed to be GhostMan.” Fred’s brow furrowed as he paused to seriously consider exactly which superhero Tadashi was supposed to be like now. The others wisely chose to ignore him.

“Well, whatever his plans are, we need to stop him,” GoGo eventually concluded.

“Yeah, but how?” Wasabi pointed out. “You saw the fight before, even with this new equipment, we can’t touch the guy, everything passes right through him. The only ones who can stop him seem to be Tadashi and Hiro, and - ”

“Oh man, Hiro!” Tadashi suddenly interrupted. “I’ve never possessed him for this long, and then with the fight - Baymax! Is he okay?”

Baymax quickly scanned Hiro’s body with a pan of his head. “Hiro Hamada is showing signs of electrolyte imbalance, which based on previous instances is a typical symptom of ghostly possession. However, his sodium levels are beginning to fall significantly, and he is experiencing mild hyponatremia. I would suggest that you replace his sodium and other electrolytes with proper food and an electrolyte solution.”

Tadashi cursed. “Okay, I’m getting out of him, now.”

“Wait!” Honey Lemon stopped him with a hand on his arm. “But once you leave, we won’t be able to hear you or see you anymore. How will we talk to you?”

Tadashi hesitated, torn. She was right, once he left Hiro he would be dead to them again. And considering they were going up against an Onryo, something they couldn’t even really touch, they would need his help to stop Callaghan. But he knew, as opposed as he was to doing so, that he could possess Hiro again if he had to. He told them as much.

Reluctantly, Honey Lemon let go of his arm. “Well, okay then. Don’t worry, we’ll take care of Hiro.”

“I’ll still be here, guys. I promise,” Tadashi told them with a warm smile. Then, once they’d all taken a big step back, he concentrated like Mochi had taught him, trying to find Hiro’s soul.

It was easier this time, now that he knew what he was doing. The now-familiar feeling of removing a tight set of clothes washed over him as he _pushed_ , and then he was free, standing there at Hiro’s side, looking out at his friends. Behind him, Baymax stepped forward to catch Hiro’s suddenly limp body. The others immediately rushed forward to check on him, to Tadashi’s fond amusement, though he was slightly put-out when Fred walked through him to get there.

“Ugh, what happened?” Hiro groaned as he came to. “Did we win?”

“Um, not exactly,” Honey Lemon hedged, tugging at her hair nervously. “Baymax, is he okay?”

“Scanning...scan complete,” the robot announced. “Hiro’s electrolyte balance is returning to normal, though his sodium levels are still low. He is otherwise unharmed.” Tadashi, unseen by all now, let out a deep sigh of relief. He hadn’t hurt his brother.

But to his exasperation, almost immediately Hiro was trying to get up, pushing away the concerned hands of the rest of the team. “Forget that!” he snapped, using Baymax’s chest for leverage to help himself up. “What happened to Krei? Did we catch him? Where’s the mask?”

“It wasn’t Krei, Hiro,” GoGo told him in clipped tones as she pushed him back down to a sitting position when he almost fell over trying to get up.

Hiro shot her a startled look, but thankfully gave up on standing for now. “It wasn’t? But he was in the footage. And he has the motive. If it’s not him, who was it?” 

The others hesitated, reluctant to reveal what they’d learned, and Tadashi winced. Between what he’d told them about his brother and listening to Hiro rant during his work on the microbots, his friends must have known that Hiro thought of Professor Callaghan as something of a hero, someone to look up to and aspire to be. To find out that the man he’d so admired had started the fire that killed his older brother? It would break him.

Tadashi stood there, running his hands through his short hair and helplessly watching his friends struggling to decide how to best break the news to Hiro, and thus break his heart.

But GoGo had always been of the mindset that it was better to break bad news now and get it over with than let someone find out the hard way. She’d always broke thing to them like ripping off a bandaid, painful, but quick, and now was no exception.

“It was Callaghan,” she told Hiro shortly, in her usual gruff manner. Tadashi wondered though if anyone else noticed the hurt and anger beneath her tone. GoGo had never been an emotional person, she liked to play things close to the chest, so for her pain to be noticeable, even that tiny bit, meant she must have been in agony on the inside. Tadashi’s heart went out to her, and he desperately wished he could throw his arms around her right then. She’d been Callaghan’s student too, after all.

But Hiro was still the main concern right now. “What?” his little brother looked at GoGo incredulously. “No, that’s impossible. Professor Callaghan died, remember? We went to the funeral!”

“He’s...dead, yes,” GoGo agreed, trying to figure out the best way to explain. A quick look at the others showed they were just as lost as she was, and Tadashi was invisible, so no help there. With a shrug, she simply told him the truth. “He’s a ghost. We were fighting a ghost.”

Hiro looked at her for a moment, stunned, before he let out a short burst of laughter. It was a harsh sound, rough, and sounded nothing like the Hiro Tadashi knew. “Very funny, GoGo. Now come on, tell me what’s _really_ going on.”

“It’s true, Hiro,” Honey Lemon quickly stepped forward to support GoGo, resting a hand on the other woman’s shoulder. “That’s why nothing we threw at him connected. And why those shadows he was controlling...the ones that have your microbots in them, we couldn’t actually get any readings on them. He’s not...human anymore.”

“But that’s...that’s impossible!” Hiro shouted, jumping to his feet. “Baymax, scan them, they obviously hit their heads in the fight.”

But Baymax shook his head. “Our friends have not suffered any cranial trauma during the battle. They are of sound mind, and are telling the truth.”

Hiro looked up at the robot with an expression bordering on betrayal. “Aw, come on, Baymax, not you too!”

Tadashi observed his brother carefully, absolutely devastated that he could do nothing but watch this, watch as his friends tried to explain what had happened and Hiro just became more and more upset. He was backing away from them slowly, shaking his head, his voice getting more and more shaky, until every third word was stuttered.

“You’re _lying!_ ” Hiro finally shouted, choking on tears. “There’s no way! Because if Callaghan came back, if he...If he’s here, then where’s...?” He couldn’t finish his sentence, but they all knew what he meant. And this was the revelation they’d all truly been dreading.

Baymax was the one to say it, to finally bring the awful truth to life. “Tadashi is here,” the robot announced soothingly, his voice never changing from its usual careful tone. Tadashi had intended him to be soothing and comforting, even in the face of horrible news that was common in health care. It was supposed to make it easier to understand and come to terms with what had happened. The soothing tone seemed callous now, in the face of Hiro’s distress.

Hiro refused to believe it. “No, he’s not,” Hiro said coldly. His expression had gone from pained to something twisted with grief and rage. “Tadashi’s not here.”

“But he is,” Honey Lemon tried to explain, but Hiro cut her off with a violent sweep of his hand.

“No, he’s _not_. Tadashi is _dead!_ He _left_ me, he was stupid and reckless and ran into that damn fire and _died!_ ”

The others fell silent at Hiro’s outburst, but Baymax was unmoved. “Tadashi is here,” he insisted again.

“ _Where?!_ ” Hiro roared as he whirled on the robot. His face was wet with tears, his eyes wild. “You keep saying he’s here, but where is he? Nowhere! He’s not here, Baymax, he never was! He’s lying six feet under in the ground right now, that’s where he is, not here! Not with me!” He punctuated each statement with another violent motion forward, until he was practically screaming into Baymax’s faceplate. But then it seemed like all of the fire in him burned out, and his shoulders slumped painfully. “He’s _dead_. He’s _gone_. If he really was here, I’d...I’d know, wouldn’t I?”

Tadashi had felt each of his brother’s words like a blow to the chest, and by now he was openly crying. Even though it was useless, even though Hiro _couldn’t_ know he was there, he still reached out. “Oh God, Hiro. I’m so sorry,” he sobbed. He hadn’t realized. He hadn’t really known how much this was affecting Hiro, how much pain his death had caused. He’d been so distracted with his own pain, his own confusion over his new afterlife, that he hadn’t really paid attention, just assuming that because Hiro was so motivated and working so diligently with his friends on these super suits that he was on the road to recovery. But now Tadashi could see that it had all been a distraction, something else to focus on instead of his own pain, and Hiro hadn’t really given himself the chance to grieve properly at all. His brother was still torn up inside, still broken and bleeding and this was all his fault.

The others had fallen silent at Hiro’s outburst, but once he’d gone quiet Honey Lemon stepped forward again. “He is here, Hiro. He is. We...we spoke to him.”

Immediately they all knew that was the wrong thing to say. Hiro’s head whipped up and he stared at her with burning eyes. “He spoke to _you_ and not _me?_ ” Hiro’s expression was a mix of anger and betrayal. Honey Lemon seemed to realize her mistake, because she quickly tried to explain, but Hiro had heard enough.

“Baymax!” he shouted, climbing up onto the robot’s back. “Home. _Now_.”

“But - ” Baymax tried to protest.

“ _Now_!”

Unable to disobey, Baymax fired up his rocket boots. The others cried out and called after him, begging him to stay, but Hiro was deaf to their calls now. He ordered Baymax to use his rocket fist to blast a hole in the ceiling, and then the two of them shot out into the sky across the bay.

Or rather the three of them, because Tadashi had always known his brother better than anyone, and he’d quickly grabbed onto Baymax’s wing the moment he realized what Hiro was about to do. He hung grimly on to the metal as the shot off across the dark water, feeling completely numb, and trying very hard to ignore the sounds of crying coming from the figure next to him.


	7. Presence

By the time they landed, Hiro had gone quiet. Tadashi kept glancing over at his brother nervously, but he couldn’t see Hiro’s face past his helmet, so he was forced to stew in his uncertainty. Hiro disengaged from Baymax’s back almost before they’d landed, hopping down to the ground and immediately stomping into the garage and booting up the surviving computer. He snarled out a string of curses when he seemed to realize that whatever he needed was on the other one, the one that Tadashi had accidentally fried. Immediately he started taking components apart, transferring wires and connectors to the other computer.

“Baymax, give me your chip,” Hiro tossed coldly over his shoulder. “There must be something wrong with it. I’m going to do a scan.”

“I do not understand,” Baymax confessed with a tilted head even as he stepped into the garage. “My internal systems are reporting no errors, and my troubleshooting software is up to date. Have I done something wrong?”

Hiro let out a harsh bark of laughter that didn’t sound amused at all. “Well, you couldn’t detect the concussions everyone seems to have, or whatever drugs they were taking, so there must be something wrong with you. Now give me your chip.”

“There were no concussions amongst my patients,” Baymax insisted. “My scanner is fully functional, and working within parameters.”

Fed up with waiting for Baymax to obey, Hiro simply grabbed a stepstool and placed it in front of Baymax so he could reach up and open Baymax’s card port himself.

But Baymax wasn’t finished. Tadashi had programmed him to learn, and that learning programming was kicking in now. The bot was determined to understand what he had done wrong. “Are you referring to the electrical anomaly that occurs within my circuits in the presence of Tadashi Hamada?”

Hiro flinched at the name like he’d been struck. He started pulling off Baymax’s chest armour, as if his hands were itching to tear something apart. His face was scrunched up, though whether in anger or distress Tadashi couldn’t tell. “Stop it, Baymax,” Hiro grunted, dropping the last piece of chest armour to the ground with a loud clatter against the concrete. “Just...just stop. He’s not here, he never was.”

“But Tadashi is here,” Baymax quickly insisted. “I am detecting the anomaly again, and the source seems to be coming from there.” The robot pointed his finger, still covered in the bulky gauntlet, to the air about a foot to Tadashi’s left. So Baymax _could_ sense him, even if he wasn’t exactly sure of Tadashi’s location. Hiro’s eyes seemed to drift to where Baymax was pointing, despite himself, and for a moment there was a flicker of hope across his features. But when he saw nothing but open space, his face hardened, and he angrily turned back to Baymax.

“There’s _nothing here_ , Baymax!” he snarled.

“Tadashi is here,” Baymax repeated.

“No, he’s not!”

“There is an anomaly - ”

“There’s nothing there, Baymax, just _stop_ it!”

“Tadashi is - ”

“Tadashi’s _**gone!**_ ” Hiro screamed, slamming himself against Baymax’s soft belly.

The garage was silent as a grave, none of the occupants daring to move. Then, Hiro started crying. Great big gulping sobs that wracked his shoulders and shook his entire body. He cried like he hadn’t since the funeral, since the day Tadashi had stood silently in their once shared bedroom and watched him break down. He howled and cried like a child, pounding his fist on Baymax’s plush chest, before slowly sinking down. Before he could fall too far though, Baymax caught him, wrapping him up in now-bare vinyl arms and holding him close while Hiro broke and finally, _finally_ grieved like he should have a long time ago.

Throughout it all, Tadashi watched silently, biting his lip to keep in his own tears, and eventually looking away when it became too painful to watch. He would have given _anything_ to be the one holding Hiro right now, patting his hair and telling him it would all be okay. But he was here, completely invisible, unable to make Hiro see him or hear him, with only Baymax really knowing he was there. God, if only there was some way he could let Hiro know, to tell Hiro he was here for him, that even if he was dead, he wasn’t gone! But the only time he could actually communicate with the living was when he was possessing Hiro, and if he was possessing Hiro then how was he supposed to talk to him if Hiro was unconscious until he woke up after and Tadashi was already - 

His thoughts were cut off when his roaming eyes landed on the computer desk, and the various items cluttering its surface. The brothers had always kept a pen and a stack of sticky notes on hand in case they had a brilliant idea out of no where and needed to write it down quickly before it faded. As he looked at them, he could feel one of those ideas springing to mind.

He quickly looked over at Hiro and Baymax, who were still embracing. Hiro was letting out the occasional choked-off sob, but otherwise was starting to calm down. Baymax was helping by patting Hiro’s head in soothing motions, and speaking to him softly.

It had been way too recent since the last time he’d done this, but if it would make his brother happy, Tadashi was willing to try anything. Besides, if anything went wrong, he trusted Baymax to keep Hiro safe. So, with a determined clench of his fists, Tadashi strode forward and got to work.

++++

Hiro was getting really sick of blacking out for no apparent reason. He came to yet again, sitting in his chair in the garage in front of the only working computer, head fuzzy with a familiar grogginess. He’d be starting to worry about all these apparent fainting spells, except Baymax had scanned him several times over the past few days and hadn’t commented on anything. Though, considering Baymax was apparently broken, maybe he shouldn’t be putting so much faith in the robot’s diagnosis.

Speaking of Baymax, the white balloon-like robot was standing there in front of him, completely out of his armour now, and watching him with his usual blank expression. Hiro looked up at Baymax for a moment, not sure what to say. On the one hand, the robot was still trying to convince Hiro that his brother was a ghost or something stupid like that, supporting his supposed ‘friends’ in their cruel joke. But on the other hand, Hiro had just broken down all over Baymax, crying like a little kid, and all Baymax had done was keep him close and offer him comfort. He could even still see a faint sheen of moisture on Baymax’s chest from where his tears had smeared over the white vinyl. So he was feeling a little mixed towards his brother’s final invention at the moment.

But after a few minutes of silence, he decided there was no point in just sitting around. He still had a villain to catch, even if he had to do it by himself.

“Hey, Baymax,” Hiro greeted tiredly. “Sorry about that.”

Baymax tilted his head. “There is no need to be sorry. Emotional outbursts are common for those experiencing grief, and can be healthy. I am just happy to help.”

“I guess,” Hiro agreed reluctantly. “Still, I - ” Whatever he had been about to say was cut off as Hiro glanced over at the computer desk and nearly choked on his own spit. The surface was absolutely _covered_ in post-it notes, the desk, the monitor, the keyboard, the wall behind. Every inch of space was plastered. “What?” Hiro murmured, furrowing his brow in confusion. With a shaking hand he reached out and plucked the nearest one off of the desk, reading it with absolute disbelief.

The handwriting was so messy and shaky, he almost couldn’t read the note. It was like two people had fought over a pen to write it, each of the letters looking slightly different from the last. But he could read it, just, and what was written there made him stop breathing for a moment.

_Still not giving up on you, little brother_

The handwriting was foreign, but those words...Hiro could practically hear Tadashi’s voice speaking them as he read, his brother’s deep warm confidence in him giving him strength. Had Tadashi left this note for him before he’d...before he’d died? But Hiro had never seen it before, and how had it gotten here? Curious and nervous at the same time, Hiro picked up another note. The handwriting was the same, but the message was different.

_I still think you’re brilliant and you’re going to do great things with that big brain of yours. You’re going to change the world._

_P.S. Risking your life by creating a superhero team, though, was not what I had in mind._

But _how_? There was no way Tadashi could have written this before the fire, they hadn’t become superheroes yet! Desperate now, Hiro started plucking up notes in a frenzy, reading them with hungry eyes. As he went through them, he noticed the handwriting changing, growing more confident, and more familiar, until the last notes were unmistakably in his brother’s hand. The familiar handwriting alone would have brought tears to his eyes, but then he read the messages.

_I’m always here for you, even if you don’t know it_

_Please let the others help you. You don’t have to do this on your own_

_I’m worried about you, and I wish so much that I could be there for you_

_Don’t forget Aunt Cass. Please, she needs you too. She’s grieving too_

_I’m sorry_.

The last note fell from Hiro’s nerveless fingers to flutter to the floor beneath the desk, where all of the others had landed. Hiro was standing there, surrounded by notes, staring blankly into space and trembling. Tadashi had written these. Tadashi had left him these notes, had contacted him from beyond the grave. There was no other explanation. But how had he done it?

He turned to Baymax, expression lost, but the robot seemed to already know what he wanted. What he needed.

“Tadashi is here,” Baymax said again quietly.

“Where?” Hiro choked out, his throat squeezing tightly with emotion.

But instead of pointing to the air again, like Hiro half-expected, the robot’s chest screen lit up. The picture was fuzzy at first, like it wasn’t quite in focus, and then suddenly it cleared, and Hiro recognized the setting as the very garage they were standing in. But more importantly, it was _him_ looking up at Baymax’s cameras in the video, though he couldn’t remember ever doing this. And more importantly, he was wearing Tadashi’s hat. His hands floated to his head in a daze, moving as slowly as if it was a dream, but when his hands met soft fabric he knew this was real. With shaking fingers, he pulled the hat off of his head and placed it reverently on the desk, staring at it in shock. He _knew_ he’d left it back up on Tadashi’s bed, the hat had been sitting there practically since the day his brother had died. Neither he or Aunt Cass had dared to move it. But now here it was, sitting on his head.

That was when the Hiro in the video started to speak.

“Is it working?” the video Hiro asked, looking both nervous and excited. His face was bright, lacking the grief that had shadowed all of Hiro’s moods since the fire, and it made him almost unrecognizable.

“Everything is in working order,” Baymax’s voice came from the video.

“Good,” video-Hiro grinned, and then suddenly chuckled in a very un-Hiro-like way, though it still sounded familiar. “I kind of feel like I should be holding up a chalk board with a number on it or something,” video-Hiro said ruefully, shaking his head at whatever he was referring to. From the way the camera tilted a bit, Baymax was a bit at a loss too. “Nevermind, bud. Thanks for the idea, by the way. This is so much faster, and my hand was starting to cramp from writing all those notes.”

That was when Hiro spotted the desk in the video behind the other him. It was covered in sticky notes. He suddenly realized that those first couple of notes had been written in a mockery of his own handwriting, like a bad forgery, or like someone using his hands…

“Oh my god,” Hiro whispered, tears pricking at his eyes yet _again_. “Tadashi?”

The Hiro in the video smiled up at the camera in a painfully familiar way, and immediately Hiro knew.

“Oh god, _Tadashi_ ,” he moaned, tears escaping to run freely down his cheeks, but then, for the first time in far too long, Hiro felt himself start to smile. It was weak, and it was watery, but it was there.

In the video, Tadashi was adjusting the hat on Hiro’s head, grumbling to himself about how it wouldn’t fit over Hiro’s poofy hair. Once he had it settled to his satisfaction, he smiled up at the camera. “Hey Hiro,” he greeted gently. It was so strange to hear Tadashi’s words and Tadashi’s tone in his own voice, but Hiro didn’t care. This was his _brother_ , it was _Tadashi_.

“Hiro I...I want to start off by saying I’m sorry. I wish I had never gone into that fire, I wish I’d listened to you. I’d give _anything_ to take it all back. To change things.” Tadashi sighed heavily, shoulders slumping and eyes slipping shut. The video was silent for a moment, the only sound Tadashi’s slow breathing as his brother gathered his thoughts. Then he looked up again, and Hiro was struck by how much he and Tadashi had really looked alike. When he was standing like that, with his shoulders back and straight, Hiro could almost pretend for a moment it was his brother’s eyes he was looking into.

“But I can’t change things,” Tadashi finally admitted sadly. “No matter how much I want to. Or you want to. But I just want you to know that I’m sorry for how things turned out. I really am. And...and even if I’m not...quite with you anymore, even if you can’t see me or hear me, I’m still there for you. I’m not gone, I’m not leaving, and I’m not giving up on you. I’ve always known that someday you’d go out and do something incredible and...and _unbelievable_ ,” Tadashi paused to chuckle a little at the phrase both brothers tended to use, “that would change the world. And I know I’m right.”

“Mind you,” Tadashi’s expression suddenly changed from melancholy to exasperated, “turning my robotics project into an armoured warrior and convincing my friends to form a superhero team was not exactly what I had in mind. But I guess it was inevitable, considering I introduced you to Fred.” Tadashi’s voice took on a hint of rueful annoyance, and Hiro couldn’t help but laugh a bit, even through his tears.

The video of Tadashi sighed again. “Hiro...I’m not going to lie, I don’t like it. I’m worried about you, and I don’t want you to get hurt, especially against the monster Callaghan has become, but...you’re old enough now that I can’t stop you. And even if I’m worried about you, and I’m seriously convinced that you’re trying to kill me _again_ with a heart attack…” Another laugh. “Well, I just wanted to say that I’m _so proud_ of you. And no matter what, never forget that I’m always going to be here for you, because I’m not giving up on you.”

“I love you, little brother.”

Hiro had to press his hand to his mouth to suppress the choked sound that wanted to escape, his free hand rising up almost of its own will to press against the screen, and the sad-but-happy smile it was showing. Tadashi was looking up at the camera with such _love_ that Hiro could almost feel his brother’s arms around his shoulders, holding him close and telling him everything would be okay. He slowly rested his forehead against Baymax’s chest screen, even as the video ended and Baymax’s belly went back to uniform white, and just stood there a moment and breathed.

When he felt like he had the strength to do so, he lifted his head again, looking up at Baymax with damp eyes.

“Thanks, Baymax,” he whispered hoarsely. The robot merely blinked and nodded in understanding.

Just then, it occurred to Hiro that his friends had been telling the truth, and that Tadashi had been with him the whole time. Which meant he was probably here now, watching over him. He was just about to ask Baymax where Tadashi was, when he heard the sounds of footsteps just outside the garage. He panicked, not having time to hide his suit or the pieces of Baymax’s armour strewn across the floor, but thankfully it was the team that appeared in the entry, silhouetted by the neon lights outside the alley.

“Hiro,” GoGo spoke up, looking him up and down as if checking for injuries. He pointedly tried to not think of why his friends might suspect he’d be hurt when he’d gone off alone after becoming very upset. He’d caught them all eyeing him nervously at some point or another, especially if he was handling anything sharp. Although annoyed that he’d lost one mother hen and somehow gained five more, including Baymax, he couldn’t help but feel a bit appreciative of how much they cared about him.

He slowly walked over to the group with his head down, looking contrite. “Hey guys. Look, I’m sor - ”

He was cut off when GoGo suddenly came forward in a burst of movement, grabbing him and pulling him tightly into her arms. Hiro froze for a second, not used to receiving physical affection from GoGo of all people, before melting into her and just taking a second to breath.

“We’re sorry, Hiro. Sorry you had to find out like that,” she murmured into his thick hair.

“No,” he shook his head, burying his face deeper into her shoulder and just breathing for a moment. “No, I’m sorry. I didn’t even give you guys a chance to explain. I shouldn’t have left like that.”

“Yeeaaaah, maybe next time you decide to get mad at us for revealing your brother is a ghost that’s haunting you, can you wait to storm off until we’re off of the big spooky island?” Wasabi yelped when GoGo let go of Hiro to jab him in the side with her elbow. “I’m just saying!” he squawked defensively.

Hiro let out a long groan. “Oh, god, Wasabi, I’m sorry!” Hiro apologized, smacking himself on the forehead. “I didn’t even think!”

But Fred was quick to intervene, waving his thickly clawed hands. “Nah, it’s all good. Heathcliff picked us up in the family chopper.”

“So, you’re not mad at us anymore?” Honey Lemon asked.

Hiro huffed and rolled his eyes. “No.”

“And you don’t think we’re crazy?”

“Heh,” Hiro shook his head, before heading back towards the computer desk and the pile of notes around the base. He picked up one of the ones that mentioned the team, and offered it to them. GoGo took it, and the others gathered around her to read the note. One by one they looked back up at him, their faces a mix of happiness and disbelief.

“Don’t worry. Tadashi set me straight,” Hiro told them ruefully. He decided not to mention the video though. It was too private, too important to him to share. Thankfully the notes were enough to explain his sudden change of heart. “So, now that I’m actually listening, can you guys tell me what’s really going on? Is it really Callaghan?”

“That’s what Tadashi told us,” Honey Lemon said, “and we found something on the island that we think confirms it. You should see this.”

Curious, Hiro took the USB stick from her and inserted it into the computer. The group gathered around as he pulled up the various video files, searching through them. Once they found Callaghan, and then shortly after Callaghan’s daughter, it all fell into place.

“Tadashi called him a vengeance ghost, a...oni?” GoGo mentioned after they’d seen the videos.

“Oni’s are demons,” Hiro absently corrected as he searched through the remaining data, trying to see if there was anything else he could use, “not ghosts.”

“He called him an Onion!”

“I...really don’t think that’s right either, Fred.”

“Wait, no, that sounds...familiar,” Hiro perked up, his data search forgotten. “A Japanese vengeance ghost...hang on.” He stood abruptly, knocking the computer chair backwards and hitting Fred in the gut. Fred doubled over coughing, but Hiro was already out the garage and halfway up the stairs to their home over the cafe. He’d suddenly had an idea, and he wanted to act on it fast.

He vaguely remembered a dusty old book that Tadashi had received from their mother long before Hiro had been born that Tadashi kept on his bookshelf in their room. When they were younger, Hiro could remember Tadashi pouring over the book’s beautiful illustrations and text, especially on days when he really missed their parents, not even reading the book so much as holding it close. He’d shown it to Hiro a few times, but when Hiro had gotten into the habit of colouring on every bit of paper he could find with his brand new markers, Tadashi had taken the book and hidden it out of Hiro’s reach. Tadashi hadn’t taken the book out in years, as far as Hiro knew, and he’d almost forgotten it existed. But he remembered a few of the pages, and the stories they contained, and something about what the others had said just seemed far too familiar to be ignored.

It almost felt like Tadashi was rushing up the stairs with him, trying to race him like old times, and Hiro took that as a sign he was on to something.

The trick, of course, would be to _find_ the damn thing, Hiro thought as he stood in the middle of their room with his hands on his hips. Although Tadashi’s area was clean and well organized, Hiro couldn’t see the book anywhere on first glance. Of course, if Tadashi had wanted to hide it from him, it would have been hidden well. As Hiro had grown older and gotten better at snooping, Tadashi had become better at hiding things from him, and it seemed like the book was no exception. With a grunt of annoyance, Hiro went to shove the divider between their sides of the room open. Just as the paper screen scraped to the side, he suddenly stopped.

Tadashi’s things had remained just as he’d left him the day he’d died. By now everything had gathered a thin layer of dust, as neither Aunt Cass or he’d had the will to move anything. Hiro dreaded the thought of messing it all up just to find one little book. He hesitated then, standing next to the screen. Maybe he could just find out what he needed to know online. There was no need to...to disturb Tadashi’s things.

But when he looked down, ready to leave, he spotted footprints in the dust that covered the floor. They were his footprints, obviously, but he wasn’t the one who’d made them. That was when he remembered Tadashi’s hat, which he’d woken up wearing. Tadashi must have come up here and grabbed it himself before making the video. When Hiro looked closer, he could see where Tadashi had rumpled the bedsheets a little in his haste to grab the hat.

That was right. Hiro had to keep reminding himself that Tadashi might be dead, but he wasn’t gone.

Still, he paused, uncertain. But then he felt the faintest warm pressure at his back, urging him forward, and Hiro somehow knew Tadashi was there.

“Okay, I’m going,” Hiro told the faint presence with a roll of his eyes, before walking into the space. The air was stuffy, and Hiro took a moment to let it air out a bit. Tentatively he walked into the room, eyes darting for anywhere Tadashi might have hidden the book. Well, the bookshelf was as good a place to start as any.

+++

Twenty minutes later, he still hadn’t found it, and he was ready to give up. He kicked out at the bed, groaning in frustration. It hadn’t been on the bookshelf, or under the bed, or in the desk, or even in the closet! He would have started to think that Tadashi had gotten rid of it, except he knew his brother would never throw anything from their parents away.

He was just turning to leave, fed up with looking, when he heard the soft sound of something scratching across the wooden floor. He paused and listened, wondering if he’d just heard things, when it came again. He turned slowly, trying to find the source of the sound, curious. Although it was probably just Mochi, Hiro couldn’t help but wonder if maybe Tadashi had finally had enough of watching him struggle and decided to lend a hand.

The scratching seemed to be coming from one of the floorboards near Tadashi’s bookshelf. As Hiro wandered closer, he could actually see the floorboard shifting slightly, like someone was trying to pull it up but couldn’t quite manage. When he dropped to his knees next to it, though, it stopped, resting still and blending in perfectly with the rest of the floor. There was nothing to mark this board as different.

But when Hiro dug his fingernails into the seams between the planks, he could feel grooves that had been dug in, and the wood lifted easily in his hands. The entire board folded back like it was on a hinge, revealing a small cubbyhole that someone had hidden beneath.

Inside was a small trove of treasures. A small stuffed Panda that Hiro had never seen before, but looked well loved. A set of wedding bands tied together with a pale blue ribbon. The first set of tools that Hiro had ever been given, that had mysteriously disappeared after he’d used them to take apart the toaster. A picture frame holding a portrait of a family of four, the baby in the picture obviously him. The book he had been searching for.

It was Tadashi’s most prized possessions. Hiro had never even realized that half of these things existed, and he pulled each one out with trembling fingers, holding them as carefully as if they were made of glass. He studied them each for a moment, figuring out what they were and what they meant. The panda must have been Tadashi’s first stuffed animal, its fur stained and matted and one eye missing, but it was still in one piece and oh so soft. The bands were his parents, which Tadashi had inherited the moment they’d died. His tools, well that was easy enough to understand. These were the things that Tadashi valued most, and Hiro couldn’t help but feel like he was invading Tadashi’s privacy. But he was pretty sure Tadashi had lead him to this discovery, so he couldn’t be too bothered by it. Still, Hiro took the time to lay each of the items carefully on Tadashi’s desk, brushing his fingers over them and smiling, before finally collecting the book and heading back down to the garage. It was time to get back to work.

+++

“Here,” Hiro announced as he walked back into the garage, book held overhead. “I think I’ve got something.”

The others, who had been trying to find stuff online in the meantime with little success, immediately rushed over, curious and eager. Hiro placed the book on one of the worktables, carefully flipping it open to the table of contents. The book was well loved, and it fell open easily, its spine cracked in many places after years of being read over and over. To his mild surprise, it was written in Japanese, which Hiro had to admit he was a little rusty in. Thankfully when he said as much, Honey Lemon quickly stepped in to help. Between the two of them, they found the section on ghosts, and started flipping through it.

They were several pages in when GoGo suddenly cried out. “There!” she said, slamming her finger between the pages to catch the spot before Hiro and Honey Lemon went too far. They quickly opened it up, and looked at the page and accompanying illustration.

“An Onryo?” Hiro asked, carefully reading the kanji at the top of the page.

“Yes! That’s it! That’s what Tadashi called him!” Wasabi said excitedly, as the others leaned in closer. They couldn’t read the description, but they could at least look at the picture.

It was an incredibly well detailed ink drawing, done in a traditional style, depicting ghostly woman draped in a white kimono, with wild black hair running down across her face. Most of her features were covered by her hair, but it had parted over her left eye, revealing a twisted face covered in angry-looking veins painted in green and violet ink. The Onryo glared up at them with hatred from the pages of the book, even as she was clawing a man in the back with long fingernails. The man’s expression was a scream of pain and fear.

“ _That_ is what Callaghan’s become?” GoGo asked, glancing around at the others. Honey Lemon was busy reading the description, but the rest were looking at her with unease. Although it was only a picture, they’d seen Callaghan in person now, and knew he was real.

“Maybe he’s a nice Onryo?” Fred tried to suggest helpfully, but one look from the others had him shaking his head.

Just then Honey Lemon finished her reading. “Hmm, there’s not too much here, but basically what it comes down to is that Onryo are Yurei, or ghosts, that can harm or kill people to extract vengeance on their enemies or those they feel wronged them in life.”

“Like Krei,” Hiro said flatly.

“Yes, that’s probably who he’s after, for what happened to his daughter,” Honey Lemon agreed. “The only other thing here that I thought might be relevant is that it is believed that some Onryo are powerful enough to cause natural disasters, or manipulate the elements themselves.”

“His shadow things!” Fred announced, pounding a fist into his open palm. “I knew there was some sort of magical force behind that! He’s probably got an amulet to control them, a black one. Maybe Onyx.”

“So he’s basically using supernatural powers is what we’re saying,” GoGo said flatly, summing up what Fred was saying with a raised brow and a pop of her bubble gum.

“Guys,” Wasabi suddenly spoke up. They looked at him, but he was looking down at his gauntlets, a look of concern on his face. “Callaghan is a ghost, and he’s using ghost powers. As cool as this new equipment is, I don’t think it’s going to cut it anymore.”

The others looked to their own equipment, realizing he was right. Fred, however, in typical Fred fashion, focused on something else entirely.

“Was that a pun?” Fred asked, grinning. “Because your lasers cut things?”

“What?” Wasabi shot him a baffled look, before realizing what he’d just said. “No. No it wasn’t!”

“Yes it was!” Fred sing-songed, throwing his arm over Wasabi’s shoulder. “You’re already making puns! Soon, your superhero banter will reach the next level!”

“Noooo!” Wasabi howled, ducking out from under Fred’s arm and running to hide behind Baymax. Fred cackled and gave chase, all the while telling Wasabi that he should just give up and accept that soon his entire dialogue would be nothing but puns and cheesy one-liners. Baymax tried to keep an eye on both of them, but because they were running around his round body in circles, that meant he was mostly spinning in place.

The others watched them for a moment, before quickly ignoring them and getting back to work.

“Okay, so what else does the book say?” GoGo asked, reaching out to flip through a few of the pages. She paused briefly on an image that looked sort of like the Onryo, only this woman looked sad and mournful rather than monstrous. The little balls of fire floating above the woman’s head also caught her attention, but she couldn’t remember why it might be important. With a shake of her head she continued to flip the pages. “Ooh, what’s this?” she asked, finding a picture of a hulking giant wearing a tiger skin loincloth and swinging a massive iron club into a man on a horse, knocking them both down.

“An Oni,” Hiro translated, running his fingers under the kanji. “Demons or Ogres, from Japanese mythology, not ghosts. Don’t worry, I’m pretty sure they’re not real.”

At that moment Hiro could have sworn he could feel Tadashi laughing at him. Choosing to ignore it, he instead flipped back to the page on the Onryo. “I don’t think this book has much more to tell us,” he said, frowning down at the illustration. “But at least we know where to start now.”

Wasabi, who had finally been caught by Fred, wandered over, ignoring Fred who was now clinging to his shoulders and listing off every bad superhero-related pun he could think of. “We still need to address the fact that _he’s a ghost_.” Wasabi pointed out. “We can’t touch him.”

“Tadashi could, when he was possessing Hiro,” Honey Lemon argued.

“Yeah, but that messed with Hiro’s electrolytes or something, didn’t it? And what happens if they get hurt? Or knocked out? Or if Tadashi can’t do it again?”

“He has a point,” GoGo said with a shrug. “I’m not okay with sending Hiro and Tadashi up against that guy alone.”

Honey Lemon wilted a bit. “I’m not okay with it either.”

Hiro would have liked to object, and insist that he and Tadashi could handle it, but the truth was he had no idea if they could. He never remembered what happened when he blacked out, when apparently Tadashi possessed him. And as much as he’d like to, he couldn’t speak for his brother right now.

“So how do we help fight this guy? Especially considering our equipment goes on the blink whenever a ghost is around, no offense Tadashi,” Wasabi quickly shot to the empty air where the group assumed Tadashi was standing.

“Isn’t it obvious?” Fred spoke up from Wasabi’s shoulders. When the others gave him blank stares, he sighed heavily before letting go of Wasabi and dramatically moving into the middle of the room. “Tadashi the ghost can fight Callaghan the ghost. You fight ghosts with ghosts! We need to harness the powers of the dead!”

“We are _not_ killing anyone!” Wasabi shrieked. The others looked equally alarmed.

“No, no, no, man!” Fred quickly reassured him. “I mean like summoning! Ouija boards! The Necronomicon! That kinda stuff!”

“Ooooor,” an unfamiliar voice suddenly drawled from the area around their feet, “you could _not_ do that, and avoid accidentally raising an army of the undead to destroy the world.”

The group looked down in confusion. Mochi looked back up at them.

“Yo,” he greeted.

“Aaah!” The entire group screamed and jumped back, except for Baymax who stayed exactly where he was and blinked.

“Did anyone else hear that?!” Wasabi shouted.

“No, we all freaked out because we’ve never seen a cat before,” GoGo shot back sarcastically. “Of course we heard it!”

“Dude, talking cat!” Fred cheered, before throwing himself down on his stomach so he could look Mochi eye to eye. “Say ‘Fred is awesome,’ Mochi! You can do it!”

The cat raised a brow at him, before brushing past and leaping into Baymax’s waiting arms, already purring as the robot started petting his head and back. “Ah, yes. Very nice.”

“Dios mio, he did talk,” Honey Lemon murmured to herself, looking pale. GoGo glanced over and quickly moved to the other woman’s side in case she fainted, although she was equally pale.

“Mochi?” Hiro spoke up hesitantly, slowly inching towards the cat. “What...what’s going on?”

“Well, my boy, there’s something I’ve been meaning to tell you and your brother ever since his passing, but I haven’t had a chance until now, what with you always running off and him chasing after. I meant to wait until you were both older, but I suppose it can’t be helped now, not if you’re going up against an Onryo.” As Mochi was speaking, he stretched languidly in typical cat fashion, from the claws on his front paws all the way to his tail. As he stretched his tail, though, he allowed it to untwine, revealing the two tails swaying out behind him. 

“Wh-what?” Hiro gasped, eyes wide.

Mochi sat up fully in Baymax’s arms, and met each of their gaping stares with a typical cat smirk. “I am a nekomata, a cat spirit associated with the dead, and I have been a familiar to your family for centuries,” he explained.

“My...family?” Hiro repeated. He inched closer still, looking more curious than afraid now. The others stayed further back, though they too were intrigued.

“Yes,” Mochi said with a sigh. “Here, perhaps you should all sit down. I have a lot to tell you.”


	8. Preparations

Tadashi had taken a seat on the burned remains of the couch, as it was the only space free, and was now staring up at Mochi in rapt attention. He vaguely recalled when he’d first shown up as a spirit that Mochi had tried to tell him something, but he’d been too freaked out by the changes to himself and the world around him to listen. But now he was ready to learn, and a glance over at Hiro confirmed that Hiro was as well.

“Well, where to begin?” Mochi thought to himself as he sat in Baymax’s arms, being held over their heads while the entire team sat around him like children about to hear a story. “I suppose it starts with the olden days. Back in our homeland, many centuries ago, the natural and supernatural worlds were much closer together. Humans could find themselves fighting Oni in the woods, or being pranked by Kitsune, or bathing in a stream with Kappa watching. It was a different time, a different world back then. The veil between the living and the dead was also thinner in this time, and Yurei were commonly spotted roaming in forests and tombs. Areas full of their power became known as Spirit Wells.”

“Yurei?” Wasabi hissed over to Honey Lemon.

“Ghosts,” she whispered back, her eyes still trained on Mochi.

“Ah.”

Mochi’s ears flicked, but he went on as if he hadn’t heard the interruption. “In these times, some families who lived too close to these Spirit Wells would sometimes become a bit magical themselves. In the case of your mother’s line, they developed the power to speak and see the dead, and over the generations, they gained the power to channel these spirits. They became mediums.”

Tadashi jolted in his seat, remembering something Mrs Matsuda had told him. “But I thought there were no more mediums?” he asked.

Mochi glanced over at him and smiled. “Why yes, Tadashi, you’re right. It’s a commonly held belief amongst our world that the mediums had all died out. You see, the power comes from the Spirit Wells, and though the power can also be passed down through bloodlines, over time we feared that the power was becoming too diluted. And as the world changes, becoming more and more modern, the Spirit Wells are diminishing. There is but one Spirit Well left that I know of in all of this country, and it is far from here. Without the Spirit Wells, the powers of the mediums faded, and the divide between the living and the dead continued to grow until we feared that it would never be crossable again.”

Mochi looked directly at Hiro now. “Your mother was the last living medium of her bloodline, perhaps the last medium in the world, and even then her power was fading. When she passed, the spirits feared that the living would never again see the supernatural world. However, _I_ believed that there was hope in you two. Her blood flowed in you, and her powers might yet as well. So I stayed with you as the family pet, keeping an eye on you and hoping for the day you powers would develop. Only they never did. I was beginning to lose hope myself, truth be told.”

“But then Tadashi died,” Hiro said, guessing the next part of the story.

“Yes, and then Tadashi died. Imagine my frustration when he finally revealed that he’d been a medium all along, but I’d never known. And by then it was too late.”

“Wait, I was a medium?” Tadashi asked, perking up in his seat. “Since when? How can you tell?”

Mochi rolled his eyes at Tadashi. “You haven’t met many Yurei yet, have you?”

“...no, not really,” Tadashi confessed after taking a moment to think about it. “Why?”

“You’re stronger than other Yurei,” Mochi explained patiently, “and you can do things they can’t. Normally it takes months to years for a Yurei to manifest, and it took you days. You are also able to move freely about the city, while most Yurei become bound to a person or place and haunt it forever. Not to mention those fire powers. That’s not typical.”

The others had been trying their best to follow along with a conversation they could only hear half of, but once again Fred had different priorities. “Fire powers?” he perked up, looking excited. “Tadashi has fire powers too?!”

“ _That’s_ what was keeping the shadows back!” GoGo announced, her eyes lighting up with realization. “Back on the island! And why it suddenly got so hot!”

“That also explains what happened to the couch,” Wasabi muttered, looking over at it. “I think.”

“And the poster in my room!” Hiro suddenly gasped, looking over at the couch too, where he was pretty sure Tadashi was sitting, based on where Mochi was looking and some inner sense. “That was _you?_ ”

Tadashi winced, even if no-one but Mochi could see him. “Heh, yeah. Mochi, can you tell him I’m sorry about that? I just...got a bit upset.”

The nekomata huffed, but grudgingly passed on the message. The others paused a moment to try to remember what Hiro was talking about, but when he reminded them of the wake, they collectively grimaced. Of course Tadashi would be a bit upset. None of them could imagine what it would have been like watching your own funeral.

“So Tadashi _was_ a medium,” Hiro eventually prompted, trying to distract everyone from bad memories and get back to Mochi’s story.

“Yes. And I was quite upset that we lost him before he could get a chance to use his abilities. But then _you_ decided to go fight an Onryo alone, and Tadashi tried to stop you, and he ended up possessing you. And that’s when I knew that not all was lost.”

Mochi jumped out of Baymax’s lap and padded across the garage floor towards Hiro, hopping up into his lap. Once he was seated to his satisfaction, he reached a paw up and patted Hiro on the forehead. “ _You_ are a medium, Hiro. Perhaps the only one left.”

“I’m a medium?” Hiro looked at the nekomata with wide eyes, swallowing thickly. “You’re sure?”

“Tadashi managed to possess you. Ghosts can’t possess normal humans, only mediums. It’s called ‘channeling.’ Anyone else, they can’t even touch.”

Tadashi watched Hiro’s face fall a bit, echoing his own disappointment. Although he hadn’t really tried to possess anyone other than Hiro yet, he’d somehow known it wouldn’t work for anyone else. Still it was unfortunate that he didn’t even have the option.

“So what am I supposed to do?” Hiro eventually asked, his voice cracking a bit with nerves.

“Do?” Mochi repeated, before smiling. “Whatever you want, really. There’s nothing that says you _have_ to do anything. But now that you’re waking as a medium, you may find that spirits and ghosts will come to seek you out, looking for help. If you wish, you can help them. If not, you can ignore them. If they become problematic, well,” Mochi chuckled darkly, his tails twitching in sinuous arcs, “that’s why your family has a nekomata as a familiar.”

Hiro let out a huge breath, looking a little overwhelmed. “Okay. Okay. I’m a medium. Cool. I guess? But how does that help us with Callaghan? He’s probably going to attack Krei any day now!”

“Mmm, no, you said you knocked his focus off?”

“Uh, his focus?”

Mochi smiled good-naturedly, his voice taking on a lecturing tone. “Onryo are powerful evil spirits, but their powers are often so volatile that they need something to act as a focus, or else they’ll tear themselves apart. From the sounds of it, the Onryo is using that mask as a focus. If you knock it off or steal it, he loses all of his power, and becomes a normal Yurei once more, at least until he gets it back. And once it’s knocked off, it’ll take him some time to regain control of his powers.” 

“But knocking his focus off or stealing it won’t be enough to stop him for good,” Mochi sighed. “If he retrieves his mask he can regain his powers easily, or he can eventually find a new focus. To stop him for real, you can try to help him complete his unfinished business, that’s the fastest way to put a ghost to rest.”

“Mmm, no, that’s not an option,” GoGo quickly disagreed. “No helping him kill Krei.”

“Agreed,” Tadashi said vehemently.

“Is is against my programming to allow harm to come to a human being,” Baymax added, backing GoGo up. A quick glance at the others showed they were also against it.

“Well, as you’ve already figured out, Hiro channeling Tadashi gives him the power boost he needs to become stronger than an Onryo, and to control his own element. You could try that.”

“Not good enough,” GoGo interrupted again. “There’s got to be some way we can be back-up. We aren’t letting the two of them go up against this guy alone.” The others nodded in agreement.

But Mochi only shook his head. “You can’t help. You’re all human, completely human. The only reason you can even hear me is because I’m in the presence of Hiro, and his power is allowing it. Without him, you would be completely oblivious to the world of the supernatural. And it’s not like he can _give_ you supernatural powers.”

Hiro’s eyes went wide in sudden epiphany, and Tadashi had to fight back the urge to groan. That was Hiro’s ‘crazy new idea’ expression. It was a look that both excited and terrified Tadashi because historically it meant that Hiro was about to make something that would blow his mind, but at least three fire extinguishers and one visit from the cops would be involved first.

“What if I could?” Hiro asked Mochi, the gears already spinning behind his mind. “What if I _could_ give them powers?”

The cat looked at him. “What?” he asked flatly. 

But Hiro was already in motion, grabbing Tadashi’s mythology book and dropping himself into the chair before the computer. He started pulling up the files of their super suits, while at the same time flipping through the book, looking for something.

“You said I’m a medium, right? But I’m also a robotics genius,” Hiro said without any hint of bragging, just a simple statement of fact. “If I can figure out how these medium powers work, I can figure out how to make them into technology. I can change these designs, make them affect ghosts. I _know_ I can. I turned these guys into superheroes once, I can do it again,” he spun back around in his chair to look at the nekomata, who was looking back with a baffled expression. “Will you help me?”

“Wha...I...well,” Mochi stuttered, looking stunned, before composing himself with a quick lick of his paw. “I suppose it can’t hurt to try,” the nekomata finally said.

Hiro _grinned_.

Tadashi rose from his seat with a sigh and a shake of his head. “I’ll start looking for fire extinguishers.”

+++

To Tadashi’s annoyance, Hiro found Mochi a much better teacher than he had, easily picking up on what the cat was saying. He tried to push away his irritation by keeping an eye on Hiro throughout Medium lessons, making sure the pair didn’t get up to too much trouble.

Mochi started taking Hiro travelling through the city late at night, while Tadashi and Baymax trailed after them to keep an eye out for trouble. Mochi would show Hiro around, asking if he could see anything different yet, and then he and Tadashi would wait with bated breath for Hiro’s response. At first, Hiro honestly couldn’t see a thing, and they’d gone home that night disappointed, but by the third night Hiro had spotted a Tengu out of the corner of his eye, and by the fifth he was able to see some of the shops that weren’t supposed to be there. He could also now sense where Tadashi was without being prompted, even better than Baymax could, but he still couldn’t see him or hear him. Mochi said it would come with time.

Bolstered by this new development, Hiro immediately started trying to translate what he could see and feel into science and engineering, making hundreds of sketches and constantly pouring over his old designs for the team’s equipment. The others helped as best they could, bringing him food regularly, encouraging him to eat and sleep and bathe, and occasionally physically dragging him off if they had to. Baymax became like a second shadow, constantly waddling after Hiro and reminding him about the importance of a balanced diet for a growing boy. Hiro would usually roll his eyes at the robot, but usually did his best to humor him.

Mochi was unconvinced that Hiro would figure out how to make it work, how to make the invisible visible, but Tadashi believed in his brother. He knew that Hiro was capable of incredible things, and that if anyone could do it, he could. And sure enough, he was proven right.

+++

The trick had come around on the fourth day when Fred, as a joke, had thrown a sheet over himself and started shouting that he would infiltrate Yokai’s forces. GoGo had thrown her shoe at him and snapped that even if Callaghan couldn’t see through the stupid disguise he’d still be able to detect his idiocy from a mile away. At that Hiro had perked up, and he’d immediately swept his entire desk clear, pulling up a blank sheet of paper and starting to write feverishly. Eight hours and three prototypes later, he had something.

“Here,” he offered it to Honey Lemon for the first test, as he’d used her helmet. The chemist slipped it over her head and settled it in place, making sure the visor was down. Once she had it comfortable, Hiro reached up and pressed a button on the underside of her right fin. The visor shimmered for a moment, a new grid shifting over it before it returned to normal. Only now it was blinking new warnings at her. She looked around the room, over at Mochi, and a red ring appeared around the cat on the visor along with a string of text marking him as supernatural, followed by a beeping noise.

“Oh! I think it’s working,” she announced happily. “It’s detecting Mochi!”

“Anything else?” Hiro asked tentatively, biting his lip.

She furrowed her brow, continuing to scan the room. “Well, no. It’s not going off for any of us, at least - oh!” But just then the red ring appeared again, hovering over an empty spot in the garage. As she watched, the ring became a target, and more warning labels popped up. “Wait, it’s detecting something else!”

“Where?” Hiro asked breathlessly.

She pointed. “There. But what’s there, Hi - oh!” Her hands went up to her mouth and she gasped. “Wait, is that Tadashi?”

Hiro beamed up at her. “Yep!” he told her happily, and then he jumped up the air in excitement. “It works, it works, it _works!_ ” he cheered, bouncing around the room in excitement, unknowingly mirroring Tadashi’s reactions when Baymax finally worked for the first time. Once he was finished, he turned back to Honey Lemon, who looked just as excited as him. “Okay, now to find out if it tracks. Tadashi?”

The red target on the visor started moving, as if following something as it walked around the room. Honey Lemon followed its movement with her finger, glancing at Hiro and Mochi for confirmation. At the sight of twin smiles, she let out a high-pitched squeal, threw off the helmet, and swept Hiro up into a tight hug.

“Ooooh! I’m so proud of you! You did it!” she squealed happily, squeezing him tight. Hiro gasped and simply hung on, although a bashful smile was growing on his face. When she finally let him go again, he was a little breathless from the force of her embrace.

Across the garage, Tadashi watched them sadly, wishing desperately he was in Honey Lemon’s place.

+++

The group had taken turns testing out their new specter-vision (Fred’s name for it, they were praying someone came up with something better before it stuck), but quickly realized this wasn’t enough. Even if they could see Callaghan and his powers better now, they still couldn’t touch him. But Hiro’s nightly walks with Mochi had given him even more ideas, and he quickly shot off into the city to collect supplies, the nekomata and his brother scrambling after and Baymax following at a more sedate pace.

Honey Lemon was the easiest to solve for Hiro. He’d spotted the little potion shop on the fifth night he’d been out with Mochi, and walked in now with the burning confidence he often brought to bot fighting. The one-eyed crone looked up at him when he walked in, gaping at the sight of a normal human in her shop.

“Are you a little lost, sweetie?” she crooned at him, her wide smile showing crooked and yellowed teeth. “Isn’t it a bit late for you to be out and about?”

Hiro ignored her patronizing tone, striding up to the counter and slamming his hands down on the surface. The effect would have been a lot more intimidating if the counter wasn’t so tall it almost came up to Hiro’s armpits. Still, his expression didn’t change, still looking at the crone with all of the bravado he possessed.

“I need potion supplies, as many as you can give me,” he informed the crone plainly.

Her single eyebrow rose incredulously, and she gave Hiro a once-over. “I...don’t sell to minors, or humans. Go home, kid,” she said dismissively.

“But you _do_ sell to mediums, do you not?” a sly voice cut in as Mochi entered the shop, Tadashi following close behind. Baymax had tried to come with them, but he was too wide to fit through the door, so he stood outside and watched the proceedings with his usual blank expression.

“A...a medium?!” the crone choked out, and she looked Hiro over again, though this time her single eye suddenly changed to a deep blood red colour. She must have seen something different, because her face broke into a wide grin. “By Hecate’s tits, he _is!_ Gracious, come in, boy, come in! Let me show you what we have!” She scuttled out from behind her counter, dragging Hiro deeper into the shop so she could show off her wares. Tadashi scrambled after them, watching the crone like a hawk in case she tried anything funny, but also insanely curious about what kinds of things a potion shop might sell. He also recognized more than a few things from Ms Matsuda’s kitchen. Mochi simply contented himself with inspecting the shop’s stash of magical cat nip and keeping an eye on Baymax.

The crone had helped Hiro pick out a few basic potion ingredients, all the things she thought a beginner might need, and with Mochi’s approval of the selection, it came time to pay. But when Hiro pulled out a huge wad of cash, most likely bot-fight winnings Tadashi grumbled to himself, the crone had pushed the money away.

“We don’t take that here,” she spat. “Dirty human money.”

Hiro gave her his best hurt expression, but before he could try to argue, the crone got a look in her eye that made Tadashi more than a little nervous. She looked...hungry.

“I could be convinced to part with all of these supplies, and as many more as you’d like, in exchange for a...token.”

“What? What kind of token” Hiro asked her, and Tadashi was glad to hear suspicion in his tone. At least Hiro was smart enough to ask what she wanted before agreeing.

“Your blood,” she told him, the hungry look growing and her eye changing again.

“Oh _heck_ no,” Tadashi growled.

“I must object,” Baymax piped up from the doorway.

“No,” Mochi said simply.

The crone chuckled darkly. “I highly doubt, furball, that the boy has anything else of value to me. So what else will it be? No blood, no ingredients.” Hiro’s expression dropped even more, and for a moment Tadashi thought he was seriously considering it. With a glare at the crone, he moved between her and his little brother, even if he wasn’t sure how much protection he could offer. There was no way he was letting her anywhere _near_ Hiro.

Thank goodness Mochi was way more experienced at this than any of them. He simply laughed right back at the crone, hopping up onto her counter so he could look her in the eye.

“You and I both know his blood is worth more than the entire stock of this store combined. No deal,” Mochi hissed, ignoring the way both Hamadas twitched in shock. Medium blood was worth that much? Tadashi pressed even closer to Hiro, starting to heard him back towards the doorway and whatever protection Baymax could provide.

But Mochi wasn’t done bargaining. He looked at Hiro consideringly, and then turned back to the crone. “A lock of his hair,” Mochi offered imperiously, “and no more. That’s easily enough to cover the cost of the supplies here, as well as set up a tab for later. Do you accept these terms?”

The crone scrunched up her face in thought. Then, after a moment’s pause, her crooked grin was back. She nodded. “I accept.”  
“Hiro?” Mochi looked to the boy next. Hiro glanced between Mochi and the crone, and up to where he could sense Tadashi standing over him.

Shrugging, Hiro agreed. “I guess that works?”

The crone pulled out a pair of ancient-looking shears from beneath the counter and scurried around to Hiro’s side. She carefully cut off a small bit of hair from the bottom of Hiro’s head where it would be less noticeable, her face screwed up in concentration as she guided the rusted metal shears. When she had finished the crone handled the hair like it was made of the finest gold as she shuffled into the back, leaving Hiro to gather up his purchases and hand a few to Baymax. The group quickly headed home, arms full of bags. Tadashi couldn’t help but keep glancing back over his shoulder long after the potion shop faded from view. It felt like the crone’s blood red eye followed them the whole way home.

+++

Fred had also been relatively simple to figure out. Hiro had been puzzling over what to do as he walked home after his second trip to the potion shop (Honey Lemon had taken one look at the supplies and potion recipe book he’d brought back, gotten a terrifying look in her eyes, and immediately made up a list of things she wanted), when he spotted the dragon across the street with his new vision. His eyes had gone jewel bright.

“Hold this,” he told Baymax, shoving the majority of his bags into the robot’s arms on top of all the other things he was already holding.

“Hiro, no,” Tadashi warned futilely. “Aww, come on,” he moaned as Hiro dashed across the street after the dragon, narrowly avoiding being hit by a car and then a centaur pulling a cart full of logs. Huffing in frustration, Tadashi jogged after him, leaving Baymax standing on the other corner with his arms absolutely full to bursting with supplies. Mochi followed at a much more sedate pace, his expression wry amusement.

“Hey there!” Hiro greeted the dragon, waving up at it. It was bigger than a bus, its head almost two storeys up, but when it heard Hiro addressing it, the dragon arched its long serpentine neck down so that it could see him better.

“Yes?” the dragon asked with a tone of mild disdain. “What do you want?”

Hiro gave the dragon his most charming grin.

A quick conversation, a flutter of Hiro’s far too thick eyelashes, and a promise of a full batch of Aunt Cass’ best Cat’s Paw Pastries later, and Hiro would soon be the proud owner of any scales, teeth, or spines the dragon shed over the next season, which would soon be incorporated into Fred’s suit. Tadashi stared at Hiro’s back as his younger brother strutted past with an incredibly smug smirk on his face, pleased with himself for making a supernatural deal without Mochi’s interference.

“Unbelievable,” Tadashi muttered, shaking his head.

“You’re telling me!” The dragon chuckled. “The Onibaba’s been going on about those pastries for _years_ and now I get a whole batch to myself!”

Tadashi carefully inched away from the dragon as it started to drool a little in anticipation.

+++

Tadashi was the one to find something for GoGo. Mochi had brought them to what Tadashi assumed was the magical equivalent of a flea market, based on all the trestle tables and booths set up, selling all sorts of wares. They’d already almost lost Baymax twice when the robot had tried to respond to what he thought was an injured patient, but who turned out to be a zombie. Eventually the balloon-like robot had caused such a ruckus that Tadashi had asked Mochi to take him home.

After almost an hour of searching, Tadashi was beginning to think he and Hiro should just go home themselves, when he’d spotted something. He’d stopped dead in his tracks, eyes lighting up, and he’d automatically called out for Hiro, forgetting that he couldn’t be heard. By the time he looked up, Hiro was almost out of sight, and Tadashi had needed to chase him down. He cursed himself for sending Mochi off, seeing as he couldn’t communicate with Hiro on his own yet. And what if something happened? He’d probably have to possess Hiro again to defend him, but he’d rather use that as a last resort.

“Hiro!” he called out again as he finally caught up to his little brother, reaching out to try to tug at Hiro’s clothes to catch his attention, but the boy was too busy staring at wonder at a bolt of fabric that shimmered like gold but looked as light as air. Tadashi sighed in annoyance and started looking around for some help.

“Hey,” he called out to the nearest shopper, a naga with scales like rubies that matched the colour of the bindi on her forehead. She looked up at him with golden eyes, the pupils thin black slits.

“Yessss?” she hissed slowly and suspiciously, shifting her basket of goods more comfortably on her hip. “What issssss it? What does a Yurei ssssuch asssss you want with the likesssss of me?”

“I’m sorry to bother you while you’re shopping, but will you do me a favour?” he asked her, giving her his best puppy dog eyes. It seemed to soften her demeanor a little bit, though she still eyed him warily.

“What isssss it?”

Tadashi jerked his thumb at Hiro. “This is my little brother. He can’t hear me, but there’s something a few stalls over I really need to show him. Can you tell him for me?”

She stared at him for a moment longer, as if waiting for some sort of trick or catch, but when he simply smiled at her again, she finally relaxed. “Very well,” she nodded. “Tell me where you would like him to go.”

“Thank you!” Tadashi bowed to her respectively, before quickly pointing out the vendor he wanted Hiro to see. The centaur’s pale grey flanks were easy to spot through the crowd.

Hiro jumped when the naga woman tapped him on the shoulder, but once she explained what had happened, he rubbed the back of his head sheepishly.

“Whoops, sorry Tadashi, didn’t mean to run off. And thanks Miss, for letting me know!”

Hiro gave her his cutest smile, all chubby cheeks and tooth gap, and she practically _melted_.

“Oh, it’s...it’s no trouble,” she quickly reassured them, the hand not holding her basket fluttering into the air towards Hiro’s face as if she wanted to pinch his cheeks. Tadashi hid a grin behind his hand. Hiro really knew how to make his youth work in his favour, that was for sure. He fought back the urge to make a comment about snake-charming.

The brothers left her to her shopping, heading back towards the stall Tadashi had spotted. When they arrived, the centaur looked up, his expression hard to read past his thick, wild beard, but his demeanor seemed stern. Hiro wilted a little under his intense stare.

“See anything you like?” the centaur asked gruffly, gesturing to the bins and tables he’d set up around himself. It was mostly horseshoes and bridles, a rack of saddles stacked behind him, but one bin in particular caught Hiro’s eye, just as it had Tadashi’s.

“How much for a pair of those?” Hiro asked, pointing at the bin.

“Three obols,” the centaur informed him. “And no haggling.”

Neither Hiro or Tadashi had any idea what an obol was, but it was a pretty safe bet that they didn’t have any. A quick peek at the other stalls showed that no one was working in human currency either.

“Do you take hair by any chance?” Hiro asked hopefully. The centaur’s glare was answer enough.

Tadashi started looking around the market, trying to come up with some way to pay the centaur. Even if they’d gone home though, he doubted they would be able to get their hands on any obols, whatever they were. If Mochi was with them, the nekomata might have been able to suggest something else, but they were on their own. Think, Hamada! Look for another angle!

At that moment, his eyes landed on something at the back of the centaur’s stall, and he had an idea. He walked forward, catching the centaur’s hard stare.

“I can’t help but notice you have what looks like a battle bot back there,” Tadashi started conversationally, glancing at his nails.

The centaur stiffened, but slowly nodded. “I have a bit of a passion for the sport,” he admitted carefully. “What of it?”

“Your bot looks a little worse for wear,” Tadashi continued, slowly wandering around the centaur’s stock of goods to get a closer look at the bot. “Having trouble fixing it?”

The centaur grumbled and looked away, shifting his hindquarters uncomfortably. “I’m one of the best blacksmiths in the country!” the centaur snapped. “I make the finest horseshoes in the world!”

“But you can’t fix the bot,” Tadashi guessed.

The centaur stared Tadashi down for a moment, and then admitted defeat with a sigh. “No, I have not been able to fix it. Metal, I understand. All those little electric bits? They confound me.” But then his expression grew hard again, and his posture stiffened. “What of it, ghost?”

Tadashi grinned and pointed at Hiro. “My brother here happens to be the best bot fighter in the city, possibly the world,” Tadashi bragged. Even though he hated Hiro’s old bot fighting habit, even he had to admit his brother was _good_. “Give him the bot and I bet he’ll have it fixed in five minutes.”

The centaur looked back at Hiro in surprise. The young medium, who had been struggling to follow exactly what was going on when he could only hear the centaur and guess where Tadashi was, instantly straightened up and gave the centaur a weak grin.

The centaur hummed and stroked his thick beard consideringly.

Twenty minutes later the centaur was once again the proud owner of a working battle bot, one with a few of Hiro’s personal touches because he couldn’t resist, and Hiro was the proud owner of three beautiful pairs of Talaria.

Hiro immediately took the winged sandals home and started fusing them to GoGo’s wheels. Tadashi groaned when he realized this would make GoGo even _faster_ , something that made GoGo’s eyes take on a scary gleam. After adding a few pairs of the tiny wings to her throwing disks as well, Hiro showed off how he’d re-programmed her disks so that they could now track and follow her targets, even if they dodged. After that GoGo’s grin had become downright terrifying.

“For once I think I’m actually glad I’m dead,” Tadashi admitted to Mochi as he and the nekomata watched GoGo trying out her new gear.

+++

Wasabi was the last to be upgraded, mostly because they’d struggled for so long to find something. They’d eventually resorted to asking around on the street, even though it mostly got them strange looks. Tadashi went looking in the rougher parts of town, not wanting Hiro anywhere near some of the creatures that lurked in the shadows, even though he still turned up nothing.

It was a pair of giggling Yuki-Onna who finally gave them an answer.

“There is a Raiju that sleeps in the trees in Buenasukayama Vista Park,” the Yuki-Onna in the blue kimono told them with a bored expression while her companion in white giggled at them behind her sleeve. “If you can sneak up on him and tug on his tail before he sees you, he must give you a bit of his lightning. But watch out. If he catches you sneaking up on him, he’ll turn around and bite you. Trust me when I say you _won’t_ like that.”

Hiro gulped thickly, but thanked the women for their help, bowing deeply in respect. The second Yuki-Onna giggled at them again, but the first simply turned and started walking away in a whirl of snowflakes, already dismissing them from her mind. Her companion had to scamper after her to catch up, squealing in annoyance all the while.

They rode on Baymax’s back to the park, landing in a clearing as far from the trees as they could get so to not alert the creature that they were hunting. Their second flight together went a lot better than the first, with a lot less screaming, Tadashi was thrilled to say. When they landed, it was early enough that their only company in the park was a Tai Chi class near the front gates, and a pair of joggers far enough away that they weren’t too worried about being spotted. After so much time being surrounded by all sorts of supernatural creatures, it was a bit jarring to Tadashi to actually just be surrounded by normal people for once. Well, normal people and this Raiju they needed to find.

It was Baymax, using the upgraded scanner in his helmet, who spotted the creature. “I am detecting supernatural activity...there,” he announced, pointing towards a copse of trees near the center of the park. Both brothers followed the line of his finger, and then gasped when they saw it.

It was what looked like a tiger made of crackling blue electricity sleeping out on a tree branch high above the ground halfway up the tallest tree in the park. Tadashi looked up at it, _way_ , way up at it, and groaned. He hated heights.

“What do you say, buddy?” Hiro suddenly piped up, digging an elbow into Baymax’s side even though he was wearing his armour. “Ready to catch a Raiju?”

Baymax looked up at the tree, studying its height and width, and most likely calculating how much damage would occur to a human should they fall. He looked back down at Hiro. “I must advise against climbing this tree. The limbs are too thin to reliably support human weight, and you may sustain injuries should you fall.”

“Relax, buddy!” Hiro scoffed, but when he started towards the tree trunk, Baymax simply reached out and scooped him up into armoured arms, holding him still. Hiro squawked indignantly, but even when he tried struggling out of Baymax’s grip, all he succeeded in doing was tiring himself out. He eventually gave up with a huff, panting slightly from his efforts.

Tadashi couldn’t stop laughing.

“Good job, Baymax!” he praised his creation, very pleased that _someone_ was still around to keep Hiro out of trouble. And even though Baymax couldn’t hear him, he thought the robot looked quite pleased with himself anyways.

“Fine!” Hiro finally snapped, pouting. “I won’t climb the tree. But we have to get up there somehow, and if we try flying, it’ll hear us coming!”

“Perhaps we should ask it to come down?” Baymax suggested helpfully with a tilt of his head.

“Ask it?” Hiro rolled his eyes. “We can’t just _ask_ it to come down, it’ll run away or something, or maybe it’ll just ignore us. I mean, it’s a giant cat right? A giant sleeping cat made of lightning, and the only reason _any_ cat will get up when it’s sleeping is if you make it get up - which we can’t because you won’t let me climb the stupid tree - or if it spots...food,” Hiro trailed off as his eyes widened. He looked over to where Tadashi was standing, an evil expression growing on his face. “Ooooh Tadaaaashi, brother dearest!”

Tadashi’s laughter cut off like someone had hit a power button. He immediately started backing away slowly, even though he really had no where to run.

“I need you to do something,” Hiro continued in his falsely sweet voice, following after Tadashi like a...well like a cat chasing its prey. “You happen to remember those old Disney films we watched as kids? And the one with the lions? And that part at the end where the meerkat and the warthog had to distract all of those hyenas?”

“Oh no,” Tadashi groaned. 

Afterward, while the Raiju was grudgingly handing over a bit of its lightning to Hiro, Tadashi stood by Baymax and glared at the teeth-shaped holes in his blazer and resolved to never play bait again. He was also thinking it was time to get a change of clothes, though he wasn’t quite sure how that worked for ghosts. He decided he’d ask Mochi sometime after they got home. After all, everyone else was getting new and improved super suits, he was going to look downright shoddy next to them. But first, he thought to himself as Hiro bounced over, a glass jar filled with impossible flickering light clenched tightly in his hands, they needed to finish getting the others ready.

“Thanks, Baymax, you were right!” Hiro chirped as he showed off his jar of lightning. “That was _much_ safer than climbing that tree!”

Tadashi glared at his brother’s back, while Baymax simply blinked in confusion.

+++

When the equipment was ready, it was time to test it. But considering they were preparing to fight a ghost that meant the only way to test it was…

“Aw man,” Tadashi groaned to himself when he realized. “This is going to suck.”

Mochi helpfully patted him on the leg, but judging by the nekomata’s grin, he wasn’t feeling _too_ badly for Tadashi. Evil furball.

It was a very good thing they’d gone back to Fred’s manor to test out their new equipment, because between the potions, dragon claws, ghost-seeking throwing disks, lightning blades, and Tadashi’s _fire_ , the Lucky Cat Cafe would have been a pile of rubble by the end of the day.

They’d started one on one against Tadashi, with Mochi providing commentary like it was some sort of sporting event so that everyone could know what was happening when they could only see one combatant. But after the third time Wasabi had managed to dodge under a weak fireball and catch Tadashi with his lightning blades, wincing all the while, he finally stopped and stepped away, switching off his blades with a flick of his fingers.

“Uh, guys? As much fun as it is to physically abuse our good friend Tadashi, and by that I mean it’s no fun at all, sorry Tadashi.” Tadashi was busy whimpering and rubbing at the brand new electrical burn on his arm, hoping it would hurry up and fade already, but he still sent Wasabi a sarcastic salute. “But I can’t help but remember that Callaghan was a lot stronger than this. He’s an Onryo, right? Doesn’t that mean he’s stronger than Tadashi, who’s just a Yurei?”

Tadashi scoffed. “Gee, thanks Wasabi.”

He had to agree with Wasabi though. While this was helping the team learn to fight something they couldn’t really see or touch, other than with their new supernaturally-enhanced equipment, Tadashi’s hitodama weren’t strong enough on their own to do more than warm the air a bit. Without Hiro’s body acting as a channel for his power and giving him the ability to actually physically connect with the living, Tadashi just couldn’t manage to offer much of a decent fight to any of them. They needed a better training method.

Mochi seemed to understand that as well, because he nodded slowly. “That is true,” the nekomata conceded. “To be honest, at this point all you’re doing is giving Tadashi bruises. You’re right, we need to switch things up.”

“But how?” Honey Lemon asked.

“Isn’t it obvious?” Hiro answered, smirking at her. “You guys are gonna face _us_ now.” He looked over almost directly at Tadashi, just a few inches too high and to the left. “What do you say, bro?”

Tadashi hesitated for a moment, as did everyone else. It was one thing for the team to fight Tadashi, who was already dead and therefore couldn’t be truly hurt, it was another thing to face off against Tadashi in Hiro’s body. But when Hiro’s excited expression started to morph into annoyance, Baymax stepped up.

“While I must object to fighting, Hiro has explained that this training will improve his emotional and physical states, as it would be considered exercise. Physical exercise is important for health, as it will lower the risk for many diseases such as diabetes and cancer.”

“Yes, but, this is...slightly different than your usual cardio workout,” Honey Lemon tried to explain.

“It’s kind of like martial arts, isn’t it?” Fred pointed out. “That’s a kind of exercise.”

“Karate makes us better health companions,” Hiro said smugly, looking back at Baymax, “doesn’t it buddy?”

“I have been told this, yes,” Baymax agreed. “I will also be monitoring Hiro’s vital signs and electrolytes throughout the exercise, as well as your own.”

“See? Baymax’ll keep an eye on me,” Hiro argued. “Come on guys, we need to do this if we want to be ready for Callaghan. Trust me?”

“Well, I...guess so,” Honey Lemon reluctantly agreed.

“If you think you can handle this, little man, we’re ready,” Fred said.

“Don’t cry if we hurt you,” GoGo told him.

“I guess it’s Tadashi’s decision,” Wasabi pointed out to the rest of the group, “seeing as he’s the one who has to do it. What do you say, Tadashi?” The group turned to where their sensors told them Tadashi was standing.

Tadashi, knowing they couldn’t hear him, didn’t bother answering. He trusted his robot, and more importantly he trusted his brother. If Hiro said he could do this, they could do this. He walked over to his little brother, reached out to Hiro’s chest, and _pushed_.

When their eyes opened, they were shimmering golden, and Hiro’s smirk only grew.

“Okay,” Tadashi told the team, who were now looking at him with a hint of nervousness. “Let’s try this again.”

They all gulped.

Training went much differently after that. Tadashi tried his best to remember how Callaghan had fought before, and tried to mimic the man as much as possible. His fire became a seething mass surrounding him, tendrils of smoke and flame reaching out to lick at the team’s feet whenever they came too close. They learned pretty quickly that individually, the team couldn’t get close enough to Tadashi to score a hit, so they quickly huddled up, created a plan, and attacked all at once. With four people plus Baymax trying to hit him, Tadashi had a much more interesting time, but he still managed to hold his own for most of the afternoon.

At one point, Fred had stopped mid-attack, staring at something over Tadashi’s head. The others quickly noticed, and stopped as well, calling out to him questioningly. Fred had simply pointed, unable to explain. One by one the rest of the team spotted it as well, until they were all looking at the space above Tadashi’s head.

“What?” Tadashi demanded, glancing at each of them warily. It could be a trick, something to get him to let his guard down. He wouldn’t put it past them, especially Fred, to come up with such an unusual tactic.

“There’s...little fireballs,” Fred pointed.

Tadashi looked up at where Fred was pointing, and immediately spotted one of his hitodama. He felt himself stiffen a little at the realization that his friends could actually see them. Before, they’d known about Tadashi’s powers, because they’d been told about them, because they’d felt their invisible heat, but Tadashi had been pouring out so much energy into his hitodama, constantly maintaining his tendrils of flame, that they must have become visible to the humans.

“Wow, Tadashi,” Wasabi murmured, stepping back a bit. “I mean…”

Tadashi felt his heart sink a little at their stares. This was the first real sign that the team could see that there really _was_ something supernatural about the Hamada brothers. Before this the only supernatural thing any of them had experienced was Mochi the talking cat with two tails, and Mochi was too soft and fluffy to be very intimidating. But a trio of unnaturally coloured floating balls of fire, that was a little bit harder to swallow.

The team stared at his hitodama nervously, like they were _afraid_ of him, and Tadashi wanted to curl in on himself and hide.

But then Fred, wonderful, wonderful Fred, broke the silence. “My fire’s cooler,” he insisted, releasing a burst of flame from the mouth of his suit as if to prove his point. The rest of the team gave Fred their usual flat looks, immediately relaxing and forgetting all about their fear.

Tadashi stared at them in happy surprise, before a wide grin broke over his face. Trust Fred to take something like this and just roll with it. He was so glad he’d brought Fred into the nerd lab all those years ago, he really was a true friend.

But he would not allow such an insult to his hitodama go unchallenged.

With a battle cry, he charged forward and tackled Fred in a full body lunge, catching the English major by surprise and knocking him back into an ornamental pond. The two landed with a huge splash that sent a wave of water up and over onto the rest of the team, soaking them all. GoGo let out an indignant yell, and then launched herself after them, tactics forgotten. Honey Lemon and Wasabi shared a shrug and then followed, laughing as they started splashing Fred and Tadashi mercilessly. Even Baymax followed them in, though he’d only taken two steps into the pond before he tripped and landed face down, his legs wiggling uselessly for a moment. Tadashi ducked away from the main fight long enough to help his robot up and teach him how to participate, and then it became every man/woman/robot for themselves

For the next ten minutes, training devolved into a silly splashing war.

+++

Training finally wound down for the day when the team could consistently take Tadashi down without him landing anything more than a glancing blow. They’d collapsed to the ground, all sweaty and exhausted, but satisfied with their work.

“Wow. I never knew how much being a superhero could _suck_ ,” Fred finally confessed once he could breathe again without coughing. “This is hard.”

“I can’t feel my legs,” Wasabi whined from the other side of the lawn. “I’m pretty sure they’ve fallen off, can someone check?”

“Oooh, my brain,” Honey Lemon moaned, rubbing at her temples. “I haven’t had to recall that many chemical equations and recipes on such short notice since that oral exam from hell in first year.”

GoGo just grunted at them all, too tired to speak.

Baymax however, was busy checking over Hiro. Tadashi had left him almost as soon as training was over, conscious of what he might be doing to Hiro’s body by possessing him, and was now hovering nearby, feeling tired as well but not willing to sleep until he knew Hiro would be okay. Mochi stood at his side, twin tails flicking back and forth like a metronome, his green eyes narrowed thoughtfully as he watched Baymax work. Thankfully Baymax finished his scan of the unconscious boy quickly and looked up.

“Hiro is once again experiencing electrolyte imbalance, but it is not nearly as severe as last time. I believe his body is becoming used to your presence, and is learning to properly compensate. He should still drink an electrolyte solution once he awakes to restore balance more quickly, and eat a full balanced meal tonight,” Baymax reported pleasantly.

Tadashi let out a sigh of relief. Heathcliff, who had taken in all of this supernatural stuff with far more calm than a normal person had any right to, suddenly appeared at their sides bearing a tray stacked high with sports drinks and snacks, as if he had been summoned. The three, Baymax, Mochi, and Tadashi, blinked at him as one.

“For the young master,” Heathcliff said with a bow, holding out the sports drink for Baymax. The robot took it gratefully, holding on to it for when Hiro woke up. Tadashi and Mochi watched Heathcliff move off towards the others to distribute the rest of the snacks.

“Soooo, what is he?” Tadashi asked the nekomata.

The cat simply shrugged. “No idea, but there’s no way in hell he’s human.”

The pair watched Fred suddenly spring up at the promise of food, his fist knocking into the tray to send its contents flying. Heathcliff reacted faster than any human should be able to, swinging his tray around in movements so fast they could only be seen as a blur, and when he was finished, everything was safely on the tray again, as if it had never been touched. He once again offered it to Fred, looking as impeccable as always.

“Yup,” Tadashi agreed with Mochi. “Definitely not human.” Beside them Baymax simply held Hiro closer, letting out a quiet hum when his patient started to stir.

+++

They’d retired to Fred’s room that night, falling over into a messy pile similarly to the night Tadashi had gone looking for them. Tadashi followed them silently, watching them all with a fond expression as they all dropped off to sleep, one after the other. Thankfully this time they’d remembered pillows and blankets themselves, so he didn’t have to tire himself out getting them comfortable.

As it was, he was already exhausted. He’d been pouring out a lot of energy all day, more than he ever had before. He was ready to just...not be for a while. But at the same time, he remembered what happened the last time he’d fallen asleep, and how much had happened when he wasn’t aware.

Mochi, who was going to head back to the cafe soon to check on Aunt Cass, paused in the doorway, looking back over his shoulder at Tadashi.

“Is something wrong?” the nekomata asked with a flick of his tails, eyes practically glowing in the dimmed lights.

“No,” Tadashi said after a moment, not looking away from his friends as they slept.

“Surely you’re tired by now?” Mochi looked at him with a tilted head. “You used up a lot of spectral energy today. You need rest.”

“Yes, but…” Tadashi hesitated, finally glancing over at the cat in the doorway. “I’m scared if I go to sleep now, I won’t wake up in time to help.”

Mochi blinked at him in surprise before his expression seemed to soften. “Oh.” he said eventually, padding back to Tadashi’s side on silent paws. When he reached Tadashi’s side, he stretched up and clawed at the bottom of Tadashi’s jacket until the Yurei caught the hint and picked him up, scratching the cat beneath his chin. The two stood there in silence for a moment, just enjoying each other’s company.

Eventually Mochi let out a satisfied hum, stretching in Tadashi’s arms. His tails curled around Tadashi’s wrist and squeezed in a gentle approximation of a hug, before letting go and curving up over his back. “Don’t worry, Tadashi. I’ll keep an eye on them while you’re sleeping. And if the Onryo attacks while you’re still resting, I’ll wake you.”

“You’re sure?” Tadashi asked, looking down at Mochi with uncertainty.

“I promise,” the nekomata said quietly.

Tadashi fell silent again for a moment as he thought about it. Then, he nodded, a single sharp jerk of his head.

With a cheshire smile, Mochi nodded back. Then he gracefully leapt from Tadashi’s arms, landing on the floor with barely a sound, and padded away, never looking back. Tadashi watched him go, and then walked over to the others. Baymax watched him approach, blinking, before tilting his head to the side a bit, offering up some space to lean against him. Tadashi flopped down against the puffy robot with a happy sigh, reaching up once to brush his fingers through Hiro’s messy mop, and then settled down into oblivion to rest for a bit.

He was smiling even as he faded.

**Notes for the Chapter:**

> We wanted to post this chapter tonight before Ikira goes AWOL for a few days to attend her grandmother's funeral. It's a bit of a longer chapter with a lot of stuff going on, but all of this buildup will pay off soon. We hope you've been enjoying Betwixt, and please feel free to drop by both our Tumblrs anytime to say hi!


	9. Goodbye

He woke what felt like only minutes later to a sharp pain in his leg. Tadashi sat upright with a howl, throwing his attacker off, clutching at his abused limb. He glared down at Mochi, who was glaring right back up at him.

“Why the heck would you do that!” Tadashi hissed at the nekomata, rubbing at the already fading claw-marks on his skin.

“I couldn’t get you to wake up any other way,” Mochi admitted with a growl. “You were sleeping too deeply.”

“Yeah, well, I’m tired,” Tadashi grumbled, fighting the urge to just roll over and go back to sleep.

“Yeah, well, Callaghan is attacking Krei’s new campus,” Mochi informed him with a sniff, his thrashing tails revealing how tense he was.

_That_ woke Tadashi up. “What, now?” He yelled, already scrambling to his feet and looking around the room for the others. They were already gone, their equipment gone with them. “They left without me?”

“You were sleeping _very_ deeply,” Mochi repeated. “I told the others to go on ahead, that you would follow once I managed to get you up. That was nearly twenty minutes ago, so we need to hurry.”

Tadashi didn’t need to be told twice. He immediately broke into a run, scooping Mochi up into his arms without breaking stride, headed for the street, cursing all the while. The others would have taken Baymax to the fight, there was no way he could catch up to them on his own. With a growl, he dug his free hand into his pocket, searching for the cool touch of metal.

“Oh man, I hope we make it on time!” he told the cat in his arms desperately, even as he pushed through the manor’s front doors and out onto the street. Mochi didn’t respond though, because even though Tadashi had only just dug the amulet out of his pocket, there was already someone standing on the street corner.

“Good lord, boy. I’m not a taxi service! If you keep this up, I’ll have to make you your own mortar!” Mrs Matsuda snapped at him. Tadashi just grinned at the old woman, happy to see her.

“Thanks for getting here so quickly,” he nodded to her, even as he scrambled towards her mortar. 

“Yes, well, someone had already contacted me, so you got lucky.” Her glare shifted to Mochi, who at least knew well enough to shrink down in Tadashi’s arms and look contrite. “You _owe_ me, cat.”

“Yes, ma’am,” Mochi responded respectfully, tails tucked close to his body.

Tadashi’s second flight with Mrs Matsuda was similar to the first, if not somehow _faster_. Once they arrived over the brand new Krei Tech campus, Tadashi didn’t even wait for her to land, already jumping out with a brief thanks tossed over his shoulder. She shook her head and shared a look with Mochi, and then the pair shot off together in her mortar, cursing the youth these days, leaving Tadashi to charge into the battle already in progress.

It was a mess. Callaghan had clearly been busy before the team had arrived, using his shadows to knock down walls and tear up the ground, sending people running in a screaming stampede away from the campus. He’d managed to snag Krei in one of the shadow tendrils, and was holding the man hostage. The team, however, had apparently arrived just in time, because Krei was still visibly struggling in Callaghan’s grip, terrified but alive. The team was keeping Callaghan distracted, enjoying every hit they scored on him with their new improved equipment. Even from a distance, Tadashi could spot bright flashes of smoke from Honey Lemon’s potions, crackling bolts of lightning from Wasabi’s blades, and the occasional burst of dragon fire from Fred. But he couldn’t see Hiro through all the smoke and dust, which left his heart pounding.

He broke into the chaos with a shout, ducking under one of GoGo’s disks with the ease of practice, jumped over a lashing shadow tendril and around a broken piece of building, searching desperately for a flash of red armour. If he could find Baymax, he could find Hiro.

It was harder than he’d expected, given how big Baymax was, but he was hindered by the constant noise and distraction of the fight. Callaghan was shouting at them, and there was the loud cacophony of things getting destroyed, but it was the whispers of the shadows that were the most distracting. They were becoming louder and louder as Callaghan grew more desperate, bordering on wordless screams, like a thousand voices growling menacingly in his ears. Tadashi did his best to block them out as he searched frantically through the rubble.

And then he saw them, Baymax using his newly-installed shields and improved sensors to knock back any shadows that crept too close, Hiro clinging to his back like a monkey. Hiro was shouting commands to Baymax, which were quickly followed, but with all the noise Tadashi couldn’t hear him. But that didn’t matter, he thought to himself as he raced towards the pair. It was time he joined the fight.

Hiro looked up as he approached, as if he could see him coming. His suspicions were confirmed when Baymax looked over as well.

“Tadashi is here,” the robot announced.

Hiro’s eyes brightened. With a grin, he disengaged from Baymax’s back, dropping to the ground and spreading his arms wide in welcome. Tadashi didn’t even slow down, racing towards his brother at top speed as if to sweep him up into his arms in a hug. They met, Hiro’s arms coming down, Tadashi pushing forward, and then they were _them_ and Tadashi felt strength flow through him once more. His eyes snapped open, already glowing to match the hitodama’s flame.

“ _...ro?_ ” Voices suddenly filled his head as Hiro’s comm in his helmet crackled to life. “ _Hiro?_ ” Honey Lemon called out again, “ _We lost you for a moment. Are you okay? We can’t see you._ ”

“ _I’ve got him,_ ” Fred called out over the comms, suddenly appearing above Tadashi’s head to drop down to the ground in front of him, “He’s okay. And - hey!” Even though Tadashi couldn’t see Fred’s face through the suit, he could still picture the wide grin growing across his face. “Look who finally decided to show up!”

“ _It’s Tadashi?_ ”

“Yeah, it’s me,” Tadashi confirmed, nodding to Fred. His hitodama flared brighter in greeting. “Someone give me a quick update, all I’m seeing is a lot of mess.”

“ _We’re coming over_ ,” GoGo announced tersely, her voice sounding a bit tired. She’d been doing the most footwork of the group, dodging in and out of Callaghan’s sight to distract and confuse him whenever he started going after the others. She’d taken every chance she’d gotten to throw her disks to try to knock Callaghan’s mask off, but so far she’d been unsuccessful. She was getting frustrated and it showed in her voice.

“ _So far, we’ve been doing better than last time,_ ” Honey Lemon started to report, the sounds in the background indicating she was on the move as well. “ _Our equipment works on the shadows, and we’ve been keeping them from escaping the campus or hurting anyone else, but we haven’t been able to reach Krei or get the mask. The shadows are too thick._ ”

Tadashi hummed to himself, the gears in his mind already setting to work. “Do we have a plan?”

“Well, we tried talking to him, but that...didn’t go well,” Wasabi said as he ran up to them, knocking a shadow tendril that was sneaking up on him back with a single swipe of his blades. “Hiro had another idea, but we needed to wait for you.”

“Sorry about that.”

“Nah, man, we get it. Besides, I’m just glad we actually have a plan for once.”

Just then Honey Lemon and GoGo arrived, both looking a little bruised, but still standing like the rest of the team. The ends of Honey Lemon’s hair were stained with oil, and GoGo’s facemask was cracked. When Tadashi took a closer look at the others, he saw that Fred’s suit was covered in tears, and Wasabi was covered in little cuts. Hiro’s body was unscathed, but Baymax’s armour was showing all sorts of cracks and dents, signs that he’d been diligently protecting his patient. Still they all looked at him with smiles, ready to act on his command.

“Okay,” Tadashi smiled back at them, so very happy that they were all there to support him, that he could still be with them despite what happened to him. He really couldn’t have asked for better friends. He pushed the wave of gratitude down for now, though. Right now, they needed to concentrate on the task at hand. “Let’s stop this guy.”

They took only a minute to lay out the plan, conscious of Callaghan golden eyes and the snaking shadows roaming over the smoke and dust, looking for them. Once they all knew what to do, they shot off in different directions, ready to play their parts.

Though there was already smoke and dust everywhere, Honey Lemon quickly thickened their cover with a mixture of two potion bottles that she smashed together. The contents met in a violent reaction that sent a thick cloud of glittering blue smoke out over the battlefield, spreading out and sinking into every crack and crevice until it was impossible to see what was going on. Impossible, that is, unless you’d received yet another of Honey Lemon’s potions earlier that allowed them to see through the smoke like it was nothing more than a fine mist.

Fred and Wasabi moved next, running through the smoke to where Callaghan was hovering above them all on stilts made of shadows. Fred used his super jumping powers to suddenly leap out of the smoke, claws bared and dragonfire spitting out of his suit at Callaghan’s face. The man gasped at the sudden attack, sweeping his arm up in defense, a shield of shadows following the movement. Fred’s claws scraped harmlessly against the shadows, blocked, but he simply pushed off of them, leaping away before they could hit him back and disappearing once more into the smoke.

Before Callaghan could go after him, Wasabi attacked next, lightning blades moving almost too fast to be seen. Callaghan once again had to form a shield, blocking Wasabi just in time. But then Wasabi upped the power to his blades, suddenly carving through the shadows like a dull blade through fabric, leaving ragged tears. Callaghan growled low in his throat, sounding more animalistic than human, and sent more shadows shooting at Wasabi like spears. The physicist was forced back, but another blast of dragonfire from Fred kept Callaghan from finishing him off.

The two continued trading off, attacking Callaghan just long enough to distract him before disappearing into the smoke, keeping the Onryo’s attention firmly focused on them. While they were busy doing that, two others were sneaking up from behind, one with slightly less stealth than the other.

Krei, who was still dangling helplessly from the shadow’s hold, looked up sharply when he saw them approach, his mouth dropping open to speak. GoGo immediately shook her head, pressing her finger to her lips in a shushing motion. Behind her, Baymax copied the familiar action, looking slightly more comical than her. Catching the hint, Krei quickly closed his mouth, eyes darting nervously to where Callaghan was currently busy trying to block another of Wasabi’s attacks, then back to them. He looked at them pleadingly, clearly terrified.

Without offering any explanation, GoGo reached down and disengaged her wheels, allowing her to walk on normal feet once more, the twin disks taking a place safely on her back. At once she started climbing up onto Baymax. The robot spread his arms upwards as high as they could reach so she could move even further, until she was standing practically eye-to-eye with Krei. She looked over the shadows holding him with a critical expression, before she seemed satisfied she’d found what she was looking for.

“Ready, Baymax?” she whispered, her voice no louder than breathing. The robot nodded.

With that, GoGo summoned one of her disks to her hand, the edge glowing with the lightning she’d borrowed from Wasabi. Her eyes narrowed, she paused just long enough to ensure her aim was good, and then she struck, throwing her disk with all her strength. The disk flew true, ripping straight through the base of the shadows holding Krei up, before bouncing off the back of Callaghan’s head and back into her hands. With the shadows severed, Krei was suddenly held up by nothing, and he fell with a short scream. Thankfully Baymax was ready, letting GoGo drop in order to catch the man. GoGo landed on her feet on the ground below with a smirk, immediately re-engaging her wheels and darting away, leading the way for Baymax to get Krei to safety.

Callaghan had been stunned by her disk long enough that when he finally regained his senses and looked back, they’d already vanished back into the smoke, Krei with them. Callaghan froze, realizing that his prey was gone.

There was a sudden lull over the battlefield. Callaghan hovered there for a moment, chest heaving like a bellows, exhausted and frustrated by their constant attacks. And now they’d stolen his prey from him. His shoulders started to shake, the rage taking over him and forcing him to clench in on himself, his back hunching. Then, with an inhuman roar that sent a shockwave across the campus and chilled every human present to their very bones, Callaghan suddenly seemed to _grow_. The shadows thickened without warning, growing darker and larger, filling up all of the spaces and pushing Honey Lemon’s smokescreen away. The battlefield became choked with them, so that the team was forced to squeeze together into a huddle, back-to-back and facing out into the shadows with Krei trapped in the middle. The shadows grew taller, looming over them like walls, their edges becoming jagged and glistening as if coated in some dark fluid. Their hissing was now like a howling wind, louder than a jet flying overhead. Callaghan stood in the center of the mass, growling at them like a beast, his clothes billowing from the force of his power.

“Uh oh. I think we made him mad!” Fred shouted over the shadows, glancing back at the group. “Now what?”

“Now?” Tadashi replied, looking back over his shoulder at Fred. He smirked. “Now it’s my turn.”

With that, he poured everything he had into his hitodama. They flared above his head like triplet suns, spinning in dizzying orbits that were impossible to track. As they spun, they circled wider and wider, until they were forming a protective ring of fire around the group. The shadows seemed to let out an enraged shriek, trying to lash out at the humans, but were unable to get past the fire. Every time a shadow tried to pierce the ring, Tadashi would gesture with a hand, and a spike of fire would rise to meet the shadow, sending it scrambling back. Callaghan let out another wordless bellow of fury, pouring more of his strength into the shadows, but Tadashi’s fire was stronger, brighter. He blocked each of the blows with ease.

Still, he couldn’t keep this up forever. Even though the team’s suits had been modified to be able to handle the heat, Krei had no such protection, and Hiro’s body would eventually give out. With that in mind, he leaned over to Baymax, close enough so that the robot could hear him but the shadows couldn’t.

“You ready, big guy?” he asked.

The robot nodded solemnly. “I am ready. As soon as there is an opening, I shall strike.”

“Good,” Tadashi said with a nod. Then he focused all of his attention on his flames so he could give Baymax that opening. Behind him, the team split their attention between watching for any shadows that got past his guard and keeping Krei from getting fried by the flames.

Though it must have been only seconds, the battle of shadow and fire seemed to go on for ages, Callaghan trying to crush them under the weight of his darkness and Tadashi pushing back with his light. There was sweat running down Tadashi’s face now, from exertion rather than his own heat, and he could feel his concentration starting to slip. There were just too many shadows for him to fight back on his own, even with all of his energy poured into the flames. There was a split second where he missed a shadow spike rising up above him like a cobra, and he paid for it. The spike lanced out, through the opening in the flames, and slashed him across the face. It would have blinded him if not for GoGo’s quick reaction time, her hand shooting out to grab him by the collar and yank him backwards. Still, it was enough for his ring of fire to falter. Callaghan let out a dark shout of triumph, his shadows already moving forward to take advantage of Tadashi’s moment of weakness.

Except by sending the shadows to attack, he’d left none to defend himself.

Baymax saw his opening, and reacted faster than any human could. His hand rose in a clenched fist, his improved armour now coated in a film of supernaturally-enhanced material, and the rocket fist launched, firing across the battlefield faster than the shadows could react and hitting Callaghan dead in the face. The mask shattered on impact, even as Callaghan was thrown backwards with the force of the blow.

The shadows suddenly fell silent, shrinking back as if stunned. The team slowly peeked around Tadashi’s shoulders, eyes wide, searching for where Callaghan had landed through the remaining dust. They spotted him a moment later, a dark shape against the rubble, groaning as he pulled himself upright. His face was a mess, lines of blackened blood running through lines of green and purple, but he looked more human now than he had before. It was enough that the team could actually recognize him now, even if he still looked slightly demonic.

Into the silence Fred cheered. “We did it!” he whooped, thrusting twin fists into the air. He immediately started performing what some people might have called a victory dance, and most others would call random flailing.

“Um, Fred?” Wasabi called out to the English Major, his voice shaking slightly. “I don’t think we won yet.”

“What? Oh man!” Fred’s dance was cut short when he followed Wasabi’s gaze, looking up and up and _up_ at the shadows around them. They had regrouped, and were somehow looking even _more_ menacing than before.

“But we destroyed the mask!” Honey Lemon screamed over the return of the shadow’s hissing, her hair whipping around her face in the sudden wind, “Why didn’t it work?”

“ _Because, you stupid girl, the mask was never the focus!_ ”

The team gaped as suddenly one of the tendrils of shadows started to morph and shift, taking on a humanoid form. They watched in horror as the shadows seemed to solidify like a chrysalis, before splitting open with a wet sound and releasing its contents. The creature inside spilled out, body slick with a dark fluid, before slowly rising to its feet.

It was an Onryo. The creature looked exactly like the picture from the book, down to the white kimono, claws, and twisted monstrous face. It looked up at them with a perverted grin, showing off crooked and blackened teeth sharpened to needle points. It rose up to its full height, and then kept rising, hovering almost a meter above the ground, the ragged ends of its kimono drifting in the wind. It had no feet.

“ _Hello, children,_ ” it greeted them with a voice that sounded like nails on a chalkboard and a grin full of knives. “ _You’ve been very naughty_.”

“What the hell are you?” Tadashi breathed, even though it was painfully clear what it was. He was just too confused by its sudden appearance to really understand. “I thought…”

The thing cackled, throwing its head back and letting loose. It sounded more like someone choking on blood than actual laughter, but its rictus grin was still firmly fixed on its face, showing how amused it was by them.

“ _Ha! The old fool? You thought_ he _was the real enemy? No._ ” It licked its lips, leaving behind an oily black residue that shone in the light of Tadashi’s hitodama. Its eyes flickered towards the little balls of flame, and then back to the group. “ _No, he was just a pawn. One in a line of many I’ve used over the years_. I _am the true Onryo._ ”

There was a moment of stunned silence as the team tried to absorb this newest bit of information. Suddenly they realized that they were once again in way over their heads.

“But then why?” Tadashi quickly asked even as his mind started working frantically, eyes darting around even as he tried to distract the creature with his questions. Mochi’s advice rang in his head, that the only way to stop an Onryo was to find its focus. But what else could it be?

The Onryo seemed to know what he was thinking though, because its blackened grin only seemed to grow. “ _Looking for something?_ ” it asked in a falsely sweet voice, fluttering its eyelashes grotesquely. Tadashi flinched. “ _Of course you are. Why do you think I used the old fool as a cover? It’s always been my way, to find some stupid newly dead with a grudge, and lend them my power for a bit. It works out so beautifully you know. They get their revenge, before I absorb them and add their power to my own, of course, and I get beautiful, beautiful chaos and destruction. And if by some miracle a priest or_ filthy medium,” it paused to spit at the ground, the blackened saliva hissing on contact with the concrete, “ _were to come along and stop me, they’d simply banish the other ghost and I’d be free to head out on my merry way, as I have been for centuries._ ”

Behind him, the team gasped and swore, realizing they’d been tricked and that they were up against something far more powerful and ancient than they’d thought, but Tadashi could feel Hiro’s heart beating in his chest, and he knew he could not allow anything to happen to his brother. No matter what.

“But there are no priests now,” he pointed out quickly, keeping himself between the Onryo and the others as it paced around their circle like a panther, only floating over their heads. “Why use the deception now?”

The Onryo laughed again, the choking, gurgling sound making Wasabi heave a little and the others nauseous. “ _Oh, mostly for old time’s sake,_ ” the Onryo confessed with a happy smile. “ _Especially now that I’ve found a new focus of my very own, one that_ no one _will be able to destroy_.” With an evil grin, the Onryo made a sweeping gesture with its clawed hands, and the shadows surged in response. All of the sudden, the base of the shadows was filled with hundreds of thousands of little glittering shapes, painfully familiar to the group.

“Hiro’s microbots,” Tadashi whispered in despair.

“ _Yessss_ ,” the Onryo hissed triumphantly, its face growing wilder by the moment. “ _A million little pieces, but they all work together so beautifully that they become one. One focus, but in so many bits it’s impossible to destroy them all. The moment I saw them I knew I needed to have them, and so I convinced the old man they would be perfect for his revenge. And when he died in his own fire, I simply took him as well. Waste not and all that. But now the microbots are mine! I am invincible! Nothing can stop me!_ ” The Onryo threw its arms into the air and roared its joy to the heavens, the shadows hissing and undulating in response.

“Excuse me.”

The Onryo’s evil laughter was suddenly cut short by a polite robotic voice. It looked down with a stunned expression, obviously unable to believe that someone had interrupted it during its victory cry. The team was looking up at Baymax as well, just as surprised.

Baymax was standing in the middle of them all, one finger raised in his typical lecturing pose, blinking up at the Onryo.

The Onryo blinked back. When Baymax didn’t immediately speak, it looked down at the others, as if asking them what the heck was going on, before looking back at Baymax. “ _Yes?_ ” it finally prompted.

“I’m sorry to interrupt,” Baymax quickly apologized, “It’s just that Hiro wanted his microbots back.”

Once again the Onryo was stunned into silent disbelief. “ _He...wants them back_.” it repeated incredulously.

“Yes,” Baymax nodded.

The Onryo scoffed at him. “ _And you expect me to just_ give them back?” it shrieked, before laughing at him. “ _As if!_ ”

But Baymax was not deterred. “Hiro expected that he would need to take the microbots back by force, and even if they were not given willingly, he would need a way to carry all of them.” The robot took a big step back from the group. His damaged gauntlets suddenly started making a charging noise, and thin crackles of electricity arced over the cracks in his armour. “And that is why Hiro ensured that there would be a way to take them back.”

With that, the charging noise seemed to reach its peak, and Baymax slammed the palms of his gauntlets together with a loud crash. His arms formed a ring, which crackled with more blue-white electricity, making a strange static noise all the while.

For a moment, nothing happened. Then there came a tiny rattling sound from the base of the shadows. The group turned to look, spotting a single microbot vibrating harder than the others, straining against the hold of the darkness. It pulled harder and harder, distorting the shadows like someone pushing through rubber, until suddenly it burst free, shooting across the space and slamming against Baymax with a tiny plink. It stuck there, unmoving.

“Oh my god. He created a giant microbot magnet! Hiro turned Baymax into a microbot magnet!” Wasabi gasped, then looked at Tadashi. “Can he do that?”

Tadashi could only shrug. He’d known nothing of this, Hiro must have been working in secret, so he had no idea how it worked. But if anyone could build a specialized magnet that only attracted microbots, it was Hiro. Once again, his little brother had surprised him.

His thoughts were punctuated by more little plinks as a few more microbots broke free of the shadows and the Onryo’s hold to attach themselves to Baymax’s armour. It sounded like very loud metallic rain, and almost looked a bit like it as the microbots started to follow, more and more coming as the Onryo’s hold weakened. Above them the Onryo floundered in the air, its sunken eyes growing wide in disbelief.

“ _No! No, stop!_ ” Its hands rose up, grasping at the microbots as they shot by, but they were moving too quickly, too strongly for the Onryo to grasp. As more left, the shadows themselves started to shrink, falling away and drooping. For the first time since the group had freed Krei, daylight managed to peek through the shadows. The Onryo hissed and fell back even further, its ripped kimono brushing the ground. “ _No! Stop, damn you!_ ”

But Baymax didn’t stop. He was nearly completely covered in microbots now, a dark sphere with only his eyes poking out the top and his armoured legs out the bottom, watching the Onryo as it collapsed down face first to the ground.

Finally, the last microbot flew through the air to land against the pile with an almost comical plink. The air was still and silent, everyone watching to see what would happen next. The shadows were gone, the Onryo alone and exposed now as it lay face first in the dirt like a child having a tantrum. Slowly, it pushed itself up on its arms, glaring up at them all hatefully.

“ _I’ll kill you for this_ ” it snarled, eyes mad with burning rage. The team readied themselves for another fight, preparing their equipment despite their exhaustion. The Onryo pushed itself up, and began stalking towards them. “ _I’ll kill you. I’ll kill you **all**! I’ll -_ ”

It was cut off when a piece of rebar, coated in dark purple flame, was shoved through its chest. It gaped down at the blackened piece of metal, face showing nothing but blank shock. The team stared as well. Then, with a sound almost like a sigh of relief, the Onryo’s eyes slipped shut, and it disintegrated, blowing away like smoke in a breeze

As the last of the Onryo vanished, it revealed the person who had finally destroyed it. Robert Callaghan met their eyes with a steely gaze of his own, his hand clenched tight around the piece of rebar he’d used to kill the Onryo. The team gaped at him in shock.

“No one messes with my students like that,” Callaghan growled. “Not on my watch.”

But then it was like all of his strength left him at once, and he collapsed to his knees, the rebar dropping to the ground next to him with the sound of ringing metal. The fire that had surrounded it before suddenly came loose and revealed itself to be the single guttering hitodama that had been floating above him before. As Tadashi watched, a twin flame slowly took shape next to it, still weak enough that he was sure no one else could see it, but growing.

The others hung back, uncertain and no longer able to see Callaghan clearly now that he was a regular ghost again. But Tadashi didn’t wait. His job here was done anyways, the Onryo defeated, so he quickly slipped out of Hiro, easier now than ever before, easy as breathing, and slowly made his way to the professor’s side. He trusted his team to take care of Hiro while he was gone, in more ways than one.

Once he reached the other ghost’s side, he knelt down next to him. Callaghan was panting and gasping for breath, as if he’d just run a marathon, and although the injuries from Baymax’s rocket fist had healed already, there were still trails of blood running down his face. But the green and purple veins had vanished with the Onryo, and now there was nothing more to Callaghan than an old man who’d lost his precious daughter.

Tadashi sat there silently, before slowly reaching out and placing a hand on Callaghan’s shaking shoulder. It was a tiny gesture of comfort, but Callaghan’s entire body suddenly shuddered at the touch, as if it was the first bit of actual contact he’d received since he’d died. When Tadashi thought about it, it probably was.

“I’m sorry,” Tadashi said quietly. “For what happened. To you. To Abigail.”

Callaghan let out a wet scoff, shaking his head. “No, Tadashi. If anything I should be apologizing to you.” He looked up at the younger man, his eyes filled with regret. “I’m so sorry Mr Hamada. You should never have gotten dragged up into this. None of you should have.”

For a moment, looking down at this broken and beaten man, Tadashi wanted to hit him. To strike out and lash out and scream and rage because it was _true_. He should never have been involved, this had nothing to do with him. And now his brother had been dragged into this strange and dangerous world and dragged all of his friends with him, and as much as Tadashi wanted to believe otherwise, there would be no turning back. He wanted to _hurt_ someone for this, to _burn_ and _scorch_ and _maim_.

But then he took a deep breath and banished those dark thoughts, letting them dissolve in the air just as the Onryo had. It wasn’t Callaghan’s fault alone that he was here. _He_ was the one who’d decided to run into the fire that night. He was just as much at fault as his old professor. And if what Mochi had said was true, then really it was only a matter of time before Hiro had ended up discovering the supernatural world around them. If anything now he had someone on the other side to look out for him, to keep him safe from threats he couldn’t see coming. So no, as much as Tadashi wanted to blame Callaghan, he couldn’t. But he didn’t know how to put all of that in words, so he simply reached out, pulling the older man into a hug.

Robert Callaghan gasped and stiffened at the unexpected action, but all too soon he melted into it, his hands coming up to grip tightly in Tadashi’s old cardigan. His breath hitched for a moment, and he squeezed tighter.

“I forgive you,” Tadashi murmured.

Robert’s eyes slid closed and he bowed his head. “Thank you.”

Just then, they heard a scuffle of a shoe against rubble, and the pair looked up. Hiro was standing there, wobbling a little with dazed eyes and leaning more on Baymax than not, but he was obviously looking for them. His eyes darted over where they’d be if they were standing, his brow furrowed in concentration. Behind him and Baymax, the rest of the team was talking quietly to Krei, who although he looked rather shaken, was nodding along to what they were saying with a serious expression. The microbots, as well as most of Baymax’s armour, had been left in a pile to the side.

“Tadashi?” Hiro called out as he pulled the helmet off of his head. “Professor?”

The two ghosts rose to their feet, both helping each other up through their exhaustion from the fight. Once they were standing, Tadashi paused just long enough to smile up at his old professor and shake his hand. And if the smile was a little wobbly and the handshake a bit too firm, Callaghan at least had the decency to not say anything.

Hiro seemed to brighten a bit when Tadashi came to stand next to him, as if drawing strength from his presence. Baymax looked down at him, blinking happily, and Tadashi reached up to pat the robot on the shoulder.

Callaghan stepped forward, bowing his head a little as he stopped in place before Hiro. “The Onryo said he’s a medium,” Callaghan mentioned, looking up at Tadashi. “Is it true?”

Tadashi nodded.

Callaghan’s entire body seemed to relax, all of the tension he’d been carrying him since he’d lost Abigail leaving him all at once. “Good. Then maybe he can...help me. I’m tired. I would like to rest.”

Although Hiro didn’t hear any of this, his expression cleared as if he knew it was time to act. A sudden hush fell over the area as Hiro stepped away from Baymax, his eyes sliding shut. His arms rose to either side of him, palms facing downward and fingers stretched to their limits. He took a deep breath, and then began to chant.

Though Tadashi was certain Hiro had never heard the words in his life, the chant seemed to fall off of his tongue as easily as breathing, filling the air with his voice that had taken on an almost haunting quality. A wind suddenly picked up, swirling around their feet, ruffling Hiro’s thick hair. As they watched, a glowing ring of light made up of a long string of strange symbols appeared around Hiro’s feet. The ring started turning, slowly at first, and then faster and faster until it looked like a solid ring. Once it was fast enough, Hiro stepped out of the ring. With him gone, the ring rose into the air, the center filling with more shimmering light until it was a shining disk in the air. Only it wasn’t a disk, Tadashi realized.

“It’s a portal,” he whispered to himself, staring at it in wonder.

For a moment, Tadashi almost wanted to go towards it, to bathe himself in its light. He could hear voices, the painfully familiar voices of his parents, laughing and calling out to him from the other side. Almost against his will, he took a trembling step forward.

But then he thought of Hiro, wonderful, precious Hiro, with his already tiny family cut down again. He thought of his promises to never leave Hiro’s side, written down a hundred times on the notes he’d left all over the desk, and spoken countless times more. He thought of Hiro, and he stopped, sinking his feet into the ground and refusing to move.

“Sorry mom and dad. Not today,” he said sadly, turning away from the portal’s tempting light, and instead looking down at his reason for staying. Hiro, his little brother, who was his whole world. How could he have ever considered leaving him?

Hiro’s eyes suddenly slid open at the sound of Tadashi’s voice, and Tadashi gasped at the sight of them. They were now blank, glowing with the same light as the portal. For a moment Tadashi felt fear, wondering just what was happening to his little brother, but then an all-too-familiar smile broke out across Hiro’s face, gentler than Tadashi was used to, but still comforting. 

Hiro turned back towards Callaghan, leveling that smile at him next.

“Do not be afraid, Robert Callaghan,” Hiro called out across from the portal in a voice not his own, his face shining in the light. “It is safe. Step into the light if you desire to rest. I believe there are many waiting for you beyond.”

Callaghan hesitated for a moment, still obviously uncertain, but then there came a voice from the portal, and his eyes grew wide. Tadashi couldn’t hear the voice clearly, nor could he see who it was from where he was standing, but the expression on Callaghan’s face was so joyful it could only be one person.

“Abigail,” Callaghan sobbed, already reaching out. A slim female hand came out of the portal to meet him, taking his hand into her own and gently pulling him forwards. There was a bright flash as Callaghan reached the portal, bright enough that they all had to look away, and then it was gone, Callaghan gone with it.

Hiro stood for a moment more, and then his eyes rolled up into his head and he fainted into Baymax’s waiting arms.

It became very quiet, no one sure what to say or what to think after all they had seen and heard. Finally, Tadashi rose to his feet, shaky and tired, but satisfied that their work was done.

“It’s finished,” he said to the quiet air with finality. He bowed to the space where Callaghan had vanished, showing his last respects for a truly brilliant man who had just fallen prey to a great darkness, and then turned and started walking away. Baymax, carrying Hiro in his balloon-like arms, waddled after him.

“Come on, Baymax,” Tadashi said tiredly. “Let’s go home.”

+++

Unfortunately Ghost was not able to finish the art in time, so there's no art for this chapter again (yet). BUT we did get some absolutely AMAZING fanart by Ash-Smash-95 on tumblr, which you can see [**here**](http://ash-smash-95.tumblr.com/post/113427647645/guys-i-colored-it-x3-ikiracake-machina-rex). THANK YOU SO MUCH, WE LOVED IT. IT'S ART OF MY FAVOURITE SCENE, I'M HONESTLY FLAILING.

Only the epilogue left, everyone! We hope you've enjoyed this story as much as we have, because honestly it's been so much fun to write. Thank you all for sticking with us the whole way!


	10. Epilogue

Fred and Wasabi grunted as the two of them dropped the massive 3D printer into its new spot, the very last piece of equipment put in its place. Hiro was on the other side of Tadashi’s old lab, now his own, shuffling papers on the desk and sorting them into appropriate piles. Most of the papers were on SFIT letterhead, greetings letters and orientation information, but the occasional sheet was old parchment or yellowing paper covered in old runes and elegant script. These went in their own pile.

Honey Lemon and GoGo were helping to set up a tiny shrine near the window, placing a stick of incense in a battered-looking holder in front of a portrait of Tadashi. Tadashi’s old hat was hung on a hook next to it, within easy reach. Although normally this would have been a solemn task, the girls were chatting happily to each other, Honey Lemon poking GoGo in the cheek playfully when the shorter woman straightened the picture to her liking. Once they were done, they turned around to look at the new lab space.

There were still little hints of Tadashi here and there. His old toolbox in the corner. One of his favourite blazers thrown over the back of a chair. His old desk had been left alone, the papers and stationery organized but otherwise untouched. The various odd projects he’d been working on before Baymax that he’d never quite finished. But the rest of the space Hiro had completely made his own.

It was a bit jarring at first to one not familiar with Hiro. While there were tools, computers and 3D printers all over the lab space, as any robotics lab should have, there were also posters of several anime and videogame characters competing for wall space with diagrams of mythical creatures and blueprints for new designs. There were also a few new traditionally done scroll ink paintings of mountains and rivers hanging on either side of the doorway. The desk was covered in screwdrivers, action figures, and potion bottles. Paper talismans hung from the shelves, pinned in place with binder clips and ragged pieces of tape. Baymax’s charging station, which was currently occupied, had been put down next to the new shrine to Tadashi, so that when Tadashi came to visit he and Baymax could chat. The entire room looked like a lab, a teenage boy’s bedroom, and a temple shrine had collided to form one mishmash. But it was perfect for Hiro, who was a bit of a mishmash himself.

The young student in question looked up from his papers at the sound of the others approaching and smiled at them. “Thanks for helping me move in, guys!” he told them gratefully.

“No problem, little man,” Wasabi said as he ruffled Hiro’s hair. “Happy to help.”

“Especially after that last run of potion ingredients!” Honey Lemon interjected cheerfully, bouncing happily in place at the thought of all the new mixtures she could come up with using her new ingredients.

“And all the new stuff you added to my suit,” Fred added, just as excited. “I am one step closer to realizing my ultimate goal of becoming a giant fire-breathing lizard at will!” He started playing the part, growling like a monster and stomping all over the lab space, much to their amusement.

GoGo watched him with a raised eyebrow, popping her gum. “I still can’t believe you thought it was a good idea to give him wings,” she muttered to Hiro under her breath.

“Heh,” Hiro rubbed at the back of his neck in a nervous gesture. “Yeah...didn’t think that one through all the way,” he admitted. “I had the parts, so I just thought I’d use them.”

The group watched Fred a moment more, wincing as his ‘monster jumps’ ended up with him crashing into a pile of boxes Hiro had thankfully unpacked already. Fred went down in a tangle of limbs and smashing of cardboard.

They all stared blankly, completely unsurprised. Wasabi let out a grumble. “I’ll go help him up,” the physicist sighed as he walked towards Fred’s indignant squawks, rolling his sleeves up as he walked.

GoGo snorted as she watched Wasabi _attempting_ to free Fred from the cardboard. Fred was flailing around so much though that it was a pretty safe bet that Wasabi would be joining him soon. “And _these_ are the idiots that protect San Fransokyo on a semi-regular basis, from threats natural and supernatural,” she said despairingly. “My god, how have we not burned the city down yet?”

“Oh, but we’re actually doing pretty well, don’t you think?” Honey Lemon quickly tried to defend, missing the fond way GoGo had been shaking her head at the others. “We’ve actually managed to save a fair number of people, and I think the supernatural community is starting to recognize us as well, aren’t they, Hiro?”

The boy, who had been busy laughing at Wasabi’s struggles, looked up at the sound of his name. “Hmm?” he asked.

“What does the supernatural side of the city think of us?” Honey Lemon repeated patiently. “Especially after we saved that baby Gryphon from the wind turbines last week?”

Hiro’s brow furrowed and he looked down at his feet as he thought about it. “Well, I’ve been pretty busy training with Mochi, getting used to the whole medium stuff, you know? It’s been keeping me pretty distracted, so I haven’t been paying much attention. But I _think_ they like us. I definitely haven’t heard anything _bad_ , mostly they’re just really confused because normal people aren’t supposed to be able to see them. Not that you guys really can, but they don’t get how the scanners I made work. Other than that I’m not sure. Maybe Tadashi would know better.”

He shrugged, unbothered. As far as he was concerned, his priority was developing his medium powers as fast as possible. Mochi said some day if he got good enough, he’d be able to see and hear ghosts just like they were regular people. So far he could still only sense Tadashi at best, and he was getting frustrated with his lack of progress, even if the rest of the supernatural world was becoming clearer by the day.

“Speaking of Tadashi,” GoGo cut into Hiro’s thoughts in her usual brusque manner. “When should we expect another visit? He hasn’t been by in a few days.”

Again Hiro shrugged, although he didn’t look at her, instead keeping his eyes on the far wall. His shoulders had suddenly become a bit tense as well, she noted to herself. Her eyes narrowed. 

“You know he doesn’t like possessing me for no reason. Besides, he’s been getting to know the creatures of the city. Keeps him busy.”

Just then there was a loud crashing sound, and they quickly looked over. Hiro snorted when he saw that Fred had somehow gotten buried in the cardboard, and had dragged Wasabi down on top of him, leaving both men floundering. Honey Lemon winced, her hands fluttering nervously around her mouth for a moment, before she shot Hiro and GoGo an apologetic look.

“I’m going to go...help,” she told them. “Sorry, one moment.”

She dashed off, leaving Hiro and GoGo alone, snickering.

After a moment of watching the new attempts to get the others unstuck, GoGo turned back to Hiro. She was about to ask him something more, when suddenly Hiro stiffened. His eyes flashed gold for a moment, and then his whole posture changed, shoulders coming back, spine straight. He smiled up at her in a familiar way. She relaxed an infinitesimal amount, her own tiny smile coming out.

“Hey Tadashi,” she greeted him quietly.

“Hey GoGo,” he said back with a grin. “Heard you talking about me, what, did you miss me?” He tossed the question over his shoulder as he walked over to the shrine near the window, snagging the baseball cap from the hook and placing it on his head.

She rolled her eyes at him good-naturedly, reaching out when he came back to help him adjust the hat over Hiro’s hair. “As if. And of course you’d be haunting us today of all days.”

“Hey! It’s not haunting, it’s...hanging out when no one can see me or hear me,” Tadashi insisted, even though they both knew that as a ghost, ‘haunting’ was exactly what he’d been doing. “And of course I’d be here today! It’s Hiro’s first day at SFIT, wouldn’t miss it for the world!”

She started teasing him about his brother complex, but just then Honey Lemon finally got the others free from the pile of cardboard, and Fred spotted the tell-tale hat on Hiro’s head.

“Dude! Tadashi visit!” he cheered, pushing past Wasabi and almost knocking him back into the boxes. Wasabi groaned in annoyance even as he followed after, Honey Lemon trailing behind and giggling. No one could stay upset when Tadashi came for a visit.

“Hey man, are you here for long?” Fred asked brightly. “Because they finally let me introduce them to the wonder that is Space Cowboys, and we’re finally up to season 4! That’s the best one!”

“Oh god, please no more of that show,” GoGo groaned, her sentiments echoed by Wasabi. Honey Lemon was too polite to complain so openly, but even her smile looked a little fixed.

Thankfully Tadashi shook his head. “Sorry, Fred. I’m just here to say hi. It’s Hiro’s special day after all, I don’t want him spending half of it unconscious.”

The group of friends drooped, but nodded in understanding.

“Next time then?” Fred asked hopefully, giving Tadashi his best puppy dog eyes. Tadashi could only laugh and nod.

“Well, we were about to head over to the Lucky Cat once we were finished here,” Wasabi explained, moving towards the door of Hiro’s lab space. “I just have to put some stuff away and grab my bag, and then I’m ready to go. You guys?”

“Same,” GoGo said, pushing past him into the lab space. Fred and Honey Lemon followed.

Wasabi looked back at Tadashi. “What about you? Gonna join us at least for the trip?”

Tadashi shook his head again. “Nah. I’m just going to say hi to Baymax and write Hiro a note, and then I’ll be out of here again.”

Wasabi’s face fell a little. “A note? Oh yeah, to let Hiro know you were here again. Yeah, that makes sense.” Tadashi was puzzled at the sudden change in his friend’s mood, but before he could make sense of it, Wasabi was already waving goodbye and leaving to pack up his things. Tadashi debated about following him for a moment, but then decided he could always look into it later.

“Ow,” he said absently as he headed over to Hiro’s desk, searching for a pen and the ever-present pad of sticky notes. He quickly scribbled a note over the sound of Baymax booting up, apologizing to Hiro for once again possessing him without warning, and telling him he was so proud of his little brother for starting at SFIT after all. He was just writing a postscript warning Hiro not to mess up his old lab too badly, when Baymax waddled over.

“Hello, I am Baymax,” the robot greeted with his usual hand wave. “Your personal healthcare companion. Hello Tadashi.”

“Hey Baymax,” Tadashi grinned up at his robot, leaving the sticky note in the middle of Hiro’s things. “How’re you doing?”

Baymax blinked at him in a way Tadashi was pretty sure meant he was smiling. “I am functioning quite well. The newest upgrades Hiro developed based on your old notes and your input have been very helpful in making me a better healthcare companion. My supernatural energy sensors have been properly calibrated and I can now accompany Hiro on his travels into the paranormal sides of the city without danger of running over others I cannot detect.”

“That’s good! I’m happy to hear that, bud,” Tadashi smiled up at Baymax. He was very proud of his creation, even if Baymax was being put to use in ways he had never intended. The nurse robot was still helping a lot of people, and really, that’s all Tadashi had wanted. No matter the method. He reached up and patted Baymax’s chest. “You’re doing a great job.”

“...Yes, I suppose I am improving.” Baymax agreed, but there was a pause, a hesitation that Tadashi almost didn’t think was possible. The robot looked down for a moment, almost as if he was uncertain, before looking back up at Tadashi. “Are you leaving soon?”

“Yeah,” Tadashi admitted, though he was starting to think he shouldn’t. Everyone had been acting strangely today, and he was pretty sure he couldn’t blame it on first day of school nerves. “I was going to let Hiro go so he can go home and tell Aunt Cass about his first day. Why?”

Baymax was silent for a moment, as if trying to gather his thoughts. The pause only made Tadashi more worried. What was going on?

“It is just that...Hiro has been suffering from a decreased mood after your visits. His neurotransmitters are usually low for a full day after.”

Tadashi stared at the robot in alarm. “I’m messing with his neurotransmitters now? I thought I only affected his electrolytes! And that wasn’t even an issue anymore!”

“I do not believe it is you possessing him that causes the problem,” Baymax quickly reassured him in his usual soothing tones. Tadashi was less than calmed though. “I believe it is that he...misses you.”

_That_ threw Tadashi off. “What? But I’m here all the time! And even when I leave, I always make sure to come back before midnight. And I visit the others as much as I can, and…”

Baymax hesitated again, unsure if he should say anything more. But then he decided that helping his patient was the highest priority, even if that meant saying something he wasn’t sure he should. Hiro had never told him _not_ to tell anyone, after all. Besides, he honestly thought telling Tadashi would be better in the long run, his information cascades running through all possible scenarios and finding this one had the best possible outcome.

“That is just it,” Baymax explained gently. “Hiro has expressed to me in private that he is experiencing jealousy towards the others. While he is always aware of your presence when you are nearby, he cannot speak to you or interact with you as the others do, as his body is the only one you can possess. I suspect the others have recognized this issue on their own, as they are usually present to distract Hiro whenever he is experiencing low mood.”

Tadashi jerked as if he’d been slapped, the truth behind Baymax’s simple explanation leaving him stunned. He’d never thought about it like that. He hadn’t even realized. He could hear and see Hiro whenever he wanted, even if Hiro couldn’t respond to him, and so it hadn’t affected him as much as his little brother. But now that Baymax brought it to his attention, he realized he’d noticed Hiro always looking a bit down after he’d been possessed. Tadashi had just chalked it up to being tired from the experience, since Hiro still occasionally took a while to wake up after Tadashi left. He cursed himself in his head. Once again he was failing Hiro.

He looked back up at Baymax with a serious expression. “Thank you for telling me this, Baymax.” The robot nodded back. “I honestly didn’t notice until now, but I think you’re right.”

Then Tadashi let out a soft sigh, frustrated. “I’m not sure what to do about this, but at least now I know. I’ll...have to look into it,” he decided after a moment. “See if I can think of something. Maybe Mochi has some ideas. Or Mrs Matsuda.”

He muttered to himself for a few seconds, trying to think of where he could go for answers. But then there was a sharp tap of knuckles against the lab door, jolting him out of his thoughts and making him jump a little in surprise.

“Yo, little man!” Fred called out through the door. “You almost ready to go?”

“Almost!” Tadashi called back. He waited until Fred’s shadow moved away before he turned back to Baymax. “Keep an eye on him for me?” he requested.

Baymax smile-blinked at him again, and nodded. “Always,” the puffy robot promised.

Then, after a quick hug, Tadashi left, slipping out of Hiro’s body, and phasing away through the wall, off to try to find a solution to this new problem. Hiro was left behind, a bit dizzy but awake, rubbing at his face. He let out a low groan as he tried to wake up his mind again, his hands rising up, until they brushed against the brim of the hat on his head. He froze, fingers tracing the worn stitches, before he gently pulled the cap off, bringing it down to cradle it in his hands.

“So Tadashi came by again?” he asked Baymax, staring at the hat with a blank expression.

“Yes,” the robot confirmed. “He has left you another note.”

Hiro didn’t respond to that. Nor did he move for a moment, too busy staring down at the hat in his hands, his fingers running over the design on the front like a priest running his hands over prayer beads. Then, in a sudden burst of movement, Hiro pushed past Baymax, heading for the shrine and the hook on the wall. He hung the hat up again with a borderline angry motion, but then immediately took the time to straighten it again almost apologetically. Then he walked out of the lab, scooping up Tadashi’s note as he passed and shoving it into his hoodie pocket to read later.

“Come on, Baymax,” he called for his robotic friend. “Aunt Cass is making chicken wings.”

“Wiiings!” Baymax cheered happily, following after Hiro at his usual pace. Hiro waited for him to pass through the doorway before reaching out and flicking off the light to his new lab space. He shut the door behind them and locked it, not looking back, a melancholy expression on his face.

+++

Hiro crawled up into his bedroom, dragging his feet up the stairs, with a happy smile on his face and a full belly. Aunt Cass had outdone herself with dinner, complimenting Hiro’s favourite chicken wings with her best takoyaki and a really tasty pasta salad. Honey Lemon had brought a few dishes of her own, and the group had ended up eating so much food they’d all needed to just sit for a while. They’d passed the time telling stories about their day, and taking turns giving Hiro advice about how to survive in college. By the time his friends had left, it was getting pretty late, and Aunt Cass had shooed him off to bed while she finished cleaning up. Hiro gave her a grateful hug before trudging up the stairs.

Baymax was waiting in his room when he arrived. The robot had spotted Mochi at one point during the evening, and had gone chasing after the cat with outstretched arms. Not wanting to say anything about the cat’s true nature with Aunt Cass in the room, Hiro had simply watched the two wander off with a shake of his head. If Mochi wanted his personal walking cat bed slash petting companion for the evening, that was fine. Hiro was distracted by all the food and laughter anyways. Although he did find it a bit strange that Mochi had come back down the stairs about an hour later, looking smug, alone. He figured once Baymax had gotten tired of petting the nekomata he’d come back down and join them.

But here Baymax was, standing in the middle of Hiro’s room like he was waiting for him to arrive. He blinked when Hiro reached the top of the stairs, waving a little.

“Hello, Hiro,” Baymax greeted. “Have the others gone home?”

“Yeah, it’s getting pretty late,” Hiro told him, moving past towards his bed and the giant pile of clothes lying next to it. With a yawn and a scratch at his underarm, Hiro stripped down, tossing his clothes onto the pile, and quickly threw on his pjs. “I’m going to go brush my teeth, and get ready for bed myself. You want a game or something to keep you busy?”

“Actually, although brushing your teeth is important for preventing cavities and tooth decay, there is something I must show you first.”

Hiro paused mid-step, halfway towards the bathroom. He looked back at Baymax in surprise and curiosity. “Show me?” he repeated, immediately turning back. While it could just be some health care video on some issue Baymax felt Hiro wasn’t taking seriously enough, he usually didn’t ask before playing them. Baymax had never asked to show him something before. He walked back over to the robot, looking up at him with a tilt of his head. “Show me what?”

Baymax didn’t respond. Instead, his chest screen suddenly lit up, starting a video. Hiro was annoyed for a split second, thinking he’d been tricked into watching a health video after all, but then he recognized his room. The video was focused on Tadashi’s side, the still-made bed the centerpoint. The lighting was strange, it looked like it was just as late as it was now, but there was a strange blue-gold glow over everything.

“Did...did Tadashi make another video?” Hiro asked, even though there was no one on screen. And he definitely didn’t remember the blackout when this would have been filmed. But Baymax didn’t answer, standing as still as a statue, so Hiro focused back on the video, his eyebrows furrowing in confusion.

He’d been watching for almost a minute with nothing happening, and was just starting to suspect that maybe Baymax and the video had frozen, when he thought he saw a flicker of something. He squinted, leaning closer to the screen. What was…

“Hiro?” a voice called out to him. Hiro froze in shock and disbelief. Although the voice had definitely come from Baymax, from the same vicinity the robot’s usual voice came from, it had sounded nothing like the smooth robotic tones Baymax usually used. In fact, it sounded exactly like…

“Tadashi?” Hiro choked out. There was no way. It had to be some kind of trick. Maybe Tadashi had programmed his own voice into Baymax as an alternative to the soothing robotic tones he usually used. Maybe it was a recording. That had to be it.

“Baymax, what’s going on?” Hiro asked, his voice shaking. His eyes seemed to be permanently glued to the screen on the robot’s chest, waiting for something to happen. Waiting for whatever he’d seen to come back. Waiting for some kind of _answers_.

He didn’t have to wait long though. As he watched, the video flickered a bit, like a TV getting interference, and then just as quickly it snapped back to normal. Except the video had changed. Instead of a simple recording of Tadashi’s side of the room, there was someone standing there now. Someone impossible. Hiro felt his breath catch in his throat.

Tadashi Hamada looked out from the screen on Baymax’s chest, glancing around a bit with a worried expression. “Is it working now?” he asked the room at large. A finger came up and tapped at the screen, making a the sound of someone tapping on glass. “Baymax? Can he hear me and see me?”

Hiro, who had frozen at the first sight of his brother, suddenly let out the breath he’d been holding in a burst of breathless laughter, his hand running through his hair in disbelief. “Tadashi? he called again.

Tadashi’s eyes immediately focused on him, and a wide smile broke out across his face. “Hey little bro,” he said. “Long time, no see.”

Hiro couldn’t even respond, too busy holding back happy tears, his hands over his mouth. He shook his head in disbelief. Of _course_ those would be the first words Tadashi would say to him since he’d died. Of _course_. Unbelievable.

To be honest, Tadashi wasn’t exactly looking stable himself. Hiro could see twin trails of tears running down his face as well, glittering in the light of the three hitodama that were dancing happily above his head. The two brothers just stared at each other for a moment, completely overwhelmed at being able to see each other for the first time in months. When Tadashi let out a not-so-quiet sniffle, Hiro gave up on trying to hold his own tears in, and just let go, crying and laughing and smiling so wide his face hurt. He threw himself at Baymax’s chest, wrapping his arms around the soft vinyl, and squeezing tightly. To his relief, Baymax’s arms came up to hug him back, though Hiro wasn’t sure if it was Baymax or Tadashi himself doing the actual hugging. It didn’t matter. It still made him feel warmer inside than he had in a _long_ time.

Eventually, once Hiro could bring himself to let go and the two of them could look at each other without setting off a fresh wave of crying, they managed to settle down, Hiro sitting on the bed and Baymax sitting on the floor. Hiro stared at his brother a moment, completely at a loss for what to say.

“Just...how?” he finally asked, running his fingers through his hair again.

“Honestly?” Tadashi laughed a bit ruefully, “A lot of trial and error. I was trying to think of some way to actually _talk_ to you, bouncing ideas off of Mochi up here, when Baymax came up and I actually bounced off of _him_. He apologized, and started talking to me, and that’s when I realized that with all of the ghost-proofing we’ve been doing on his circuits, he’s kind of become a bit of a supernatural entity himself. And I mean, I put a lot of myself into him, whether I meant to or not, and _you’ve_ been doing a lot of work on him, and we’re both mediums, or at least I was and…” Tadashi trailed off a bit, realizing he was rambling. He rubbed the back of his neck and ducked his head a little, suddenly a bit embarrassed. “Well, I figured it was worth a shot.”

“And it worked,” Hiro breathed happily, fighting the urge to reach out and hug the robot again. If he did, they’d probably be up all night trying to calm down again, and as much as he’d like to pretend otherwise, he still had class tomorrow.

“Yeah. It worked,” Tadashi agreed. His expression softened, taking on a hint of sadness. “I’m sorry I didn’t try this before now. It wasn’t fair to you, always missing out.”

Hiro quickly shook his head, too happy to think back on his earlier jealousy. “I’m just happy you’re here now. How long can you stay?”

Tadashi glanced around the screen, almost like he was looking around inside Baymax’s innards. “Well, I haven’t noticed any issues yet with Baymax’s circuits, but I probably shouldn’t stay too long. If he’s anything like you, I’m probably doing _something_ to him.”

Hiro suddenly snorted, hiding his giggle behind his fist. “I can’t believe you turned your nursing robot into a medium.”

“Hey!” Tadashi objected with a laugh, shaking his head. “You turned him into a battle bot first! And wow, yeah, I didn’t even think of that.”

“Imagine if we started mass producing him like _this_. We can advertise them as ‘Baymax, your Personal Health Care Companion Slash Medium. Can patch up your paper cuts _and_ tell you what Grandma thinks of your new haircut!’ We’ll be rich!” He fell back against the bed laughing at the thought, Tadashi laughing almost as hard.

“Could you imagine? Mochi would _freak_ ,” Tadashi added, setting Hiro off again. The two laughed together like old times, like the nights past when they’d both been lying in bed in the darkness, whispering to each other across their shared room and trying not to wake Aunt Cass with their giggles. They didn’t bother to hold it in now, though, too happy to care.

Eventually they did both calm down, though, Hiro lying on the bed and just breathing for a moment. There were still tears running down his face, but he was pretty sure if he said they were from laughing so hard, Tadashi would agree with him. He was an awesome brother like that. Hiro’s eyes slipped closed for a moment, and he focused on his own breathing, feeling the rise and fall of his ribs.

“Hiro?” Tadashi eventually called out, breaking their tentative silence.

“I’m just sleepy,” Hiro confessed, eyes still closed.

“Oh.” And then, “Should I go then?”

Without opening his eyes, Hiro reached out and grabbed Baymax’s hand, gripping it tight. “Stay?” he asked quietly. “Just until I fall asleep?”

Tadashi huffed softly, and Hiro could just picture him shaking his head. “Of course, little brother.”

“Thanks, nii-san,” Hiro murmured, already drifting off, a smile on his face.

Although he was almost completely asleep, Hiro still felt it when Baymax got up, his rubbery arms shifting Hiro around until he was lying the proper way on the bed and pulling up the blankets to tuck him in. The last thing he remembered was the feeling of a vinyl face pressed against his forehead in a mimic of a goodnight kiss, warmer than the material would normally be.

“Goodnight, Hiro. I love you.”

Hiro dreamed that night of flying and ghost fire and a warm hand in his, a familiar smile guiding him as he walked into a brand new world beyond his own, and all of the wonders it contained. And when he woke the next morning, tired but happy, the feeling of a hand still in his grasp, he knew he couldn’t wait for what was to come.

**Notes for the Chapter:**

> So for the record, the scene where Tadashi pops in for a visit was the actual initial idea for this fic. EVERYTHING ELSE came about as a set up for that moment, because Ikira doesn't understand the concepts of limits or self control. Ah well, worth it.
> 
> The last image was also the art that started it all, and provided a lot of the early inspiration. We figured it was fitting to include it in the epilogue.
> 
> Well, this is the end guys. Betwixt is over and finished...or is it? Well, we may add on an additional chapter later, which will include a glossary of all the supernatural creatures and characters that popped up, as well as a few more potential tidbits for anyone who's curious. But more importantly, we know we've left a few loose ends, which....may need to be addressed at a later date. And that's all we're going to say about that ;)
> 
> Finally, a HUGE thank you to everyone who read, left kudos, commented, and made art for this fic. You guys are amazing, every one of you, and we really appreciate your messages and the time you've taken to let us know you liked it. We read every comment and count every kudo, and it really helped keep us going. So once again THANK YOU ALL, YOU ROCK OUR SOCKS!
> 
> See y'all next time!

**Author's Note:**

> Whoo hoo! So excited to finally post this!
> 
> This is based on Machina-Rex's Ghost!Tadashi AU idea on Tumblr that just grabbed me and wouldn't let go. It was a blast getting to write this together and see all the awesome arts made for the AU. If all goes well there should be illustrations in later chapters.
> 
> Come check us both out on Tumblr if you'd like! Ikiracake.tumblr.com and machina-rex.tumblr.com


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